Hey baconfry!
I know you're busy with the Gamejam, so please come back to this later, but I wanted to say how good this game is! I'm not a fan of stuffing, normally, but the anticipation and the progression is top notch, exactly like you stated in your goals in the first paragraph.
Everyone is clamoring to request more content in terms of bigger sizes, more babies, breast growth, etc, but I completely understand that it is out of the scope of the game and gets to the point where making a sequel might be better/easier to accommodate those things.
I'm going to clamor for content of a different type: Reactions. More text reactions of what the girl feels, her anticipation of growth, her struggle on stream and off, reactions during stream (maybe actions during stream that are purely text based? Maybe descriptions of masturbation/toys [at least when she's small enough to manage it, part of the progression would be how stream actions change as she gets bigger], orgasming on stream, maybe a random event where a stream viewer 'donates' a big food item [basically a hamburger twice as big as normal], stream roleplay about pregnancy and pretending there are more babies than there really are). You can even fake some of the requests by giving text descriptions of the character's body every few nights (describing weight gain, breast growth, squirming uncomfortably at night, being pinned beneath a huge belly, maybe the character thinking about her impending birth).
Maybe a short intro would be nice too: did the girl get pregnant on purpose? Was she planning on becoming a bloated whale, or did her latent desires to mukbang streaming lead her there unintentionally?
I said above that I'm sympathetic to how hard it is to add animations and bigger sizes, but I have an idea that might be more rewarding and easier to achieve than just 'bigger belly'. I think this game could benefit from a finale- just a cut away at max size (maybe achieved by purchasing a $5000 medication to delay labor or whatever seems appropriate) where you can show the character in a special render in different clothes, different pose at her final size, not having to worry about growth animations or how the old clothes fit. Bonus points if the animation shows breathing, kicks, stomach rumbles, and contractions- and give the player a chance to poke her belly, breasts, and keep feeding her (no mechanical effect, just an animation) as a reward. This would help with the problem of getting new sizes to fit with the current rig since I'm thinking a separate special final scene, and give a statement to the player "This. This is the maximum size, this is the culmination." A fade to black, description that the character is taking a break from stuffing, and buttons to get pregnant again (from scratch) or get very pregnant (keep money and unlocks).
Good luck on the game jam, and great job on an excellent belly expansion game!