I've got a question about favor and skill points; are they used to gate content or to pick what content you get? For example; if I have low favor with a character will that prevent me from getting certain scenes with them or will it give me a bad scene (a rough dom scene for example)?
I am not a fan of content locking. So, the favor system is in the game primarily to tell you what kind of stuff a specific girl likes, which in turn lets you (as a player) later decide if you want to please her, act bratty, or straight up piss her off (which might lead to a different scene). Secondly, it might unlock additional romantic scene variations (just like skills do). Generally speaking, there won't be any mechanic that will lock you away from the content - the favor system, skills, etc., serve to provide alterations to the scenes, not to punish the player for not following one specific route.
The favor will later serve for non-erotic content. Lot of favor with Ginny = better prices with certain dealers on the Market. A lot of favor with Lise = faster Tech skill gain. Tessa = more pleasant interactions with some characters outside the station, etc.
Similar applies to non-sexual skills - if you have, say, high enough Guns, you will be able to use them when needed. This might lead to a variation of the scene. These will play a bigger role when you start doing the spacer profession on a higher level. In Parts 2 and 3
(not to be mistaken with Releases), there will be many more non-sexual skills (each tied to one of the main ladies), and you will be able to pick which specialization you would like to follow. Like Salvaging with Tessa, Piloting with Lise, First Aid with Iris, etc. and combinations of thereof. The challenges that will come later will give you a chance to resolve them with these skills. In case you fail on that, the scene will get a different variation - but with little content locking as is physically possible.
The "Bad" endings will be mostly telegraphed in advance and basically serve as a tool to give you some extra scenes that lead to the end of the adventure. However, they won't be tied to skills/favor but rather your own decisions.
That said, I already know that many of them won't be particularly "bad" on their own. Yes, they will end the game, but considering their nature and me going the full "God, I wish that were me" meme when writing them, I think lots of people will enjoy them as well.
You are correct about the skills!