The Naughty Captain, your game is amazing. You do a great job with dialog, and the story keeps the player on the edge of their seat, always wanting to know more. Great job.
I think the dialog heavy approach is great. I never mind more renders, but what you have is a good balance. Also, all your characters are so sexy and appealing, it is impossible to just pick one, so multiple saves are needed, which is fine.
Overall, I love your game, a lot, but I wanted to offer some constructive perspective.
For me, looking at a walkthrough, takes about 90% of the fun out of the game. It takes a natural story, where you want to play however you naturally want to, into a mechanical exercise. Just my opinion, but I know I am not alone.
Regarding all the endings, I am a bit torn. I like seeing multiple options in a story, even bad ones, though it is very emotional to watch, because it makes you want to try again and do things differently. But in your case, I think you might have over-did it a bit. It is very difficult not to get the bad end without a walkthrough if you are trying to be with Cassie and Eve. There are a couple of choices that are not at all obvious, even if you look closely at the points given for each choice.
The walkthrough is invaluable with this game, but I think having to follow a walkthrough at all takes a lot of the fun and spontaneity out of the game. Personally, I think that the game should be more "fair" and not make the player have to meticulously follow a walkthrough to get the ending they are looking for. It should be clear to the player, using logical thinking, how make choices in order to get the path they are looking for.
A few specific examples:
The choice "This morning was very difficult to handle", during Day 4, is a big one. It is not at all obvious why this is the required choice, other than looking at the walkthrough. And if you don't choose this, you are locked into the bad ending.
Another day 4 example, you have to pick "I don't accept it". The other option "If you haven't come to me last night." seems like a completely reasonable option for the path the player is looking for, and you don't find out until much later, that you are locked into a bad ending, and no way, without a walkthrough, to figure it out, at least using logic.
Also, the choices you have to make to get an Eve only or Cassie only path are not clear either. Especially the one where you have to lie about being a virgin. It isn't revealed until much later, that this will lead to the Eve only route, so without a walkthrough, or playing the game 100s of times (which isn't fun for most people), you would never know.
Like I said, I love your game, and I can't wait to play more, but I think it would be much improved if you removed or changed the "unfair" and "tricky" (from a player's perspective) choices that lead to a bad or non-clear to the player path.
If the player has to consult a walkthrough, the game has missed the mark, in my opinion.