This is a really cool concept, and I can definitely see the inspiration from Eat the Dungeon. The story behind it is really unique and one of this game’s strongest points. You have a great foundation for it being “very bare bones” as you said. The gameplay is quite enjoyable, if not a tad hands-free. It feels a lot like a mobile game or Facebook game, but it doesn’t have the annoying energy-based thing that a lot of those types of games have.
For improvements, it’s hard to say exactly what could be improved on, since chances are most of what I do have to say here are already on their way to being improved. That being said, the weight gain feels a little… off. Like, they almost exclusively gain it in their stomachs even when they’re not full (though I did notice the bit that was added to their face which was a nice touch). Having it spread out more would greatly benefit the game. Or having each doll gain it in different ways (I could see Aria (I think that was her name… the starting doll) being all-around in terms of gain, whereas Rosa feels like one who would be more like hourglassy with a small potbelly to me, for example) (and don’t feel obligated to follow the part in parentheses, as that was just what I pictured for them - you may have other ideas that would work just as well or better and I wouldn’t want to be the reason that changes).
Also, while the gameplay was enjoyable overall, I also felt it wasn’t really involved enough. It kind of felt like I just clicked to start a level and it was all done for me. Now if I remember correctly, there are things I can do as a player besides just sit back and watch, but it was all done well enough that I really didn’t feel like I had a reason to do anything. Making the food more difficult to (b)eat or the recovery cost money would be a great way to incentivize using the combat to its full potential if you wanted this to be the way combat works in the finished project. If not, then I anxiously await what you have in mind for it instead.
All-in-all, this is a fantastic start! I look forward to playing this game more as it progresses!
EDIT: One more thing I forgot to mention! It would be cool if each doll had their own strengths. I mean, Rosa seemed to have a Spicy resistance from my own experience, but it was unclear what exactly that meant. Having more clear-cut and pronounced differences between dolls is something I feel would be a nice improvement.