There are a number of bad ends to I Love Daddy, but all of them are at the logical end of a storyline,
No, they are in the last update, this is different.
So the end where Cath and your mother run away together feels out of place, because they never go on to deal with the family issues.
And why should they absolutely goes on a deal with the family issues ?
You've two main path for the ending. Either the daughter love her mother and accept to share daddy, or she don't love her mother and try to keep daddy for herself. In the first path, the mother will try to solve the family issues. Not for her, but because she don't want that her own daughter have to live with this Damocles sword above her head.
But in the second path, why should she care ? She past the ten last years hopping that one day her daughter will turn her husband, the love of her life, back into his old self. Then, it didn't happened. Worse, her daughter stole the heart of her husband and don't care about her... The mother lost everything, her hope, her husband and her daughter. That's why she run away and why she don't need to solve the family issues. In fact it can even be seen as a revenge ; she run away and so will continue to avoid the consequences, while they are now full facing them since the family is, more or less, reunite again. As alternative, you have her falling for Cate. She lost everything, but in exchange found another love. She don't care of anything else, the traitors (the daughter and her husband) can die, it doesn't matter for her.
There's no weakness in this second path. In fact it's more well wrote than the ones where she became a whore. Whatever it's her being a real bitch and using sex to have whatever she want, or the one where she became the university sperm bucket, they are both weak. Those ending happen because she was too obsessed by the idea to have sex with her daddy and with only him. How the hell she goes for this exclusive obsession to having sex with every single guy she cross is a mystery.
It looks like you were tricked by the moment where the endings were introduced in the game. The ones that came two/three updates before the last update, you see them as weak. And the real weak ones, you see them as natural because they came with the last update.
Would the author have put few useless scenes to let him release all the endings at the same time, or even just froze these paths, that you would have probably see them differently.
But, this all happens along the end routes of the game, you made it through all the other content, got some different scenes, but they weren't necessarily bad scenes.
Like I said, no. The happens in the last release, but it doesn't mean that the other one didn't happened at the end route of the game. The game doesn't end with its last update. It's the writing of the game that end at this moment, and they are two different things.
Let say that tomorrow I release my first game, a basic seduction/corruption sandbox game. Because it's my first game, I'm not confident enough, and I don't know the engine enough (well image that I don't know it enough). So, I decide to focus on the seduction path. And because I focus on it, as well as because it took me time to understand how to do what I want for the corruption path, it will end before the last release.
Will this make this ending weak ? Just because I finished to write it before I finished to write the other path ? There's no reason for this... absolutely no reason for this.
This however, is not the end of the game. It's a premature end that shows that the dev didn't think this line through. An example of this kind of ending exists in the original version of Vis Major. By being too willing to get fucked Cara ends up kidnapped and in a dungeon and raped before finally being put out of her misery.
Are you sure about this ? I mean in a global perspective, not especially for this game.
You are a looser who's want to fuck the girl next door. One day, you find a way to blackmail her, and you do so. Then, you face two possibilities. Either you blackmailed her because you are awkward as fuck and don't saw another way to have sex with the girl you're in love to, or you blackmailed her because you are an abusive freak who jumped on the occasion. In the first path, you force her to sex, but you act gently, you think about her pleasure and, with the help of Stockholm syndrome, she fall in love with you. In the second path, she collect evidences to make you face the consequences of your actions, and you end in jail.
Obviously, the second path will end way before the first one. But is it really a poor writing ? You see the story. First panel the cops come to his house. Second panel they arrest him. Third he's in jail. Fourth he face a judge. And it continue like this with few panels until you see him, miserably sat in jail, or even raped why not. This with a good writing explaining the panels.
There's no reason to see this ending as weak just because the game will still have ten release for the gentle path.
What would have been, and is, a poor writing, the mark of a writer who "didn't think this line through", is when the author decide to not care about the consequences.
You act like a jerk, and it change absolutely nothing in your relation with the girl. Every morning you greet her with a, "shut the fuck up, stupid bitch", but like you do all the chores during the rest of the day, it doesn't matter, you still have enough points. It will yet be sexy time this night.
How can this be a better writing than making the said girl being more and more angry, more and more reluctant to have sex, until the day she kick you out of the house ? Just because writing this make it that the player will reach the end of the game while there's still many updates for the other paths ?
I'm pretty sure that it's the opposite. The game tell you many stories, and some are shorter than the other. That's all, and it doesn't mean that the shorter stories are weaker that the longest one.
It's parallel stories, but not necessarily parallel writing, nor stories that should absolutely have the same length.
Transposed to a book, the pages aren't vertically split with the gentle path at the top of the page, and the abusive one at the bottom of it. It's more a "choose your own adventure" book (even for interactive visual novels), where each page (I simply) is dedicated to one path. At the end of this page, you don't continue with the following one, you jump somewhere else in the book. And when you read the last physical page of the book, you aren't reading the end of the story.
Because they are released by successive updates, games feel like the first representation, while they in fact are like the second one. And yes, here you can feel a premature ending as a problem or a weakness. You look at the top of the page, where the story you were reading is, and see only blank. This will the bottom part of the page is still filled for many pages.
But it's just a feeling, not a reality , this in the perspective of a good written game, obviously.
Imagine, if instead the game had forced you to continue from there, now your goal, because you'd fucked up, is to escape, [...]
In the "you end in jail" ending of the blackmail path, you can let the player try to find a way to escape. You can invent an universe where jails aren't unisex, and the MC seduce some girl prisoners, some girls guardians, and achieve to escape. This just to make this path continue until the last release.
But you understand that it's now a totally different story, right ? The story told by this game is "you're a MC and you want to fuck the girl next door", not "fuck your way out of jail". It can be a good story for a game (it is a good story for a game), but it's not this game's story.
The author don't continue the game here, he started a new one inside the previous one.
Using your example of the abused girl. Maybe have the consequence be that you start to become more controlling over her. Maybe you visit this friend and scare them away. Maybe you make the girl stay at home with you. Maybe you kill the friend. Maybe you arrange a scenario where the abused girl gets assaulted and you show up as the hero.
Like me, you want coherent stories, so...
Like the vast majority of abusers, MC's just a fucking coward that finally found someone weaker than him ; hey, he used and abused of her trauma instead of just trying to win her heart like he could have.
If you try to control her more when you feel that she's ready to run away, she'll run away faster ; unless you unchain her. If you visit her friend, the said friend will send the cops over you ; do you really think that you can scare someone who already fight hard against you ? If you kill the friend, you'll awake something strong in the girl, don't think that it will end well for you. Don't think that she'll come back to her submissive self after you killed the only good thing that came in her life.
As for the hero's scenario... Sorry, but honestly it's the worse of all the options you gave. Even in a fiction it feel weak, this said it's the only one in accord with the MC personality. In all the options, you are trying to artificially continue the story. But with this one you even use a giant blinking neon sign to explain it to the player ; whatever he'll do, you'll make it that the path will end in the last release only, even if for this you need to sacrifice your pride.
But why ? Because you're too afraid of some players reaction ? Because you really want them to continue to love you ? To support you ? Because you feel that you aren't a good enough writer if you let the story naturally die ?
Except for the first one, it's the opposite that will happen. If your game is really well wrote, the players will use a previous save, or ask for one, and continue playing. They'll try to change their fate, now that they know that they fucked up. They'll do it simply because the game is well wrote and they want to know what happen if they don't mess it.
By letting the story naturally die, you proved that you master every part of it. It's not the story who lead you, forcing you to use all reanimation tools you can found to keep it alive. No, it's you who lead. You saw that it reached it's logical end, then you do what you can to let it die peacefully ; accompanying it with love until its last point.
It's a premature ending, in regard of the other path of the story, but it doesn't mean that it's a bad one, nor a weak one. You don't have to feel bad because you finished the game before the other players, you have the right to feel glad to have played a good story with a rational and logical ending.
I watched a movie yesterday where a father's PTSD and other issues force him to flee civilization. [...] It's a really sad story. And it's exactly what should be happening in your scenario.
But once again it's a totally different story that you added to artificially continue this path of the game. You'll prove that you are a good writer, that you can come to a way to fill the blank if needed... But, here again, for what reason ?
Let the player have it's part in the story. If they want to imagine that the MC run after the girl and apology, camp in front of her door for days, offering her a beautiful and expensive gift each day until she understand that he really love her, that he really care for her, let them have this possibility.
Like I said in my previous comment, every ending is a "game over". Whatever if it's the natural end in the last update, a natural but premature one, or one that came because of bad choice, they are all "game over". And once the game is over, the story is not yours anymore. It become the player's one, it's up to him to continue the story in his head. Don't force him to have your version of what happen next, let him live it the way he want it, it's his time now.
There's a reason why authors talk about the stories they wrote as their children ; it's the same process. They write the story like they raise a child, but in both case come the time where you have to let them go, to let them live their life on their own. Some child will stay near to you, some other will decide to travel the world and you'll not see them as often as you want. It doesn't man that you've failed with one or the other, it doesn't mean that one love you more than the other. It's just the way life goes.
In the particular case of game's writing, it's like raising twins. Don't expect them to have the exact same life. You'll raise them in parallel, but it can happen that one will goes on his own way, while the other one still feel the need to stay for some times. It's just natural and doesn't mean that you failed somewhere. It's not because one of the twin found the love of his life and so go live with her, while the other continue to live in your house, that you messed it.
The same apply for your stories. Some will end faster than the other, but it doesn't mean that you didn't wrote them well ; it's the way they goes, and it doesn't matter if a story end before another.