I think exploring either 1 or 3 is going to be a valuable effort. Ofc, could always add more variety like personalities and other options, but I think adding some strategy into the game would be worthwhile.
A lot of what is done in the game gets the player instant dopamine with seeing the characters weight go up, as well as the different interactions they have. All of the little minigames besides the one where you answer questions supplement that. But if you push that dopamine bump to the side it feels like the game's missing some depth with gameplay.
Maybe consider adding more repercussions with pushing these characters to gain weight. The game reaches a point where I can just hook these characters I meet line and sinker without any trouble. A bit of conflict would go a long way.
Something else I don't see brought up here (kind of with personality-specific events), is that while I love to explore the differences between each of these characters and what they have to say, how the interactions go etc., sometimes especially with the minigames I've noticed that the written descriptions are the same no matter who you interact with. Adding more options makes the minigames less cumbersome, especially when it comes to the late game.
Love the work! Excited to see what you produce nonetheless.