I saw a bug where you could still interact and even transfer size to a patient, despite them being gone. (I think) Their mouth and hair were at the far right of the room when this happened
Also, i saw the comment you made with "that_guy_yeah". I'm more than willing to help with the art for free! Just be warned that I'm not the best at drawing making fetish art.
Making it multiplayer would probably be difficult, since I've never seen a game like this ever have online integration. If you are going for a website route, though, you might wanna just go the extra mile and make the entire game it's own website. It'll probably give you less coding restrictions as well.
First idea: sandbox mode. Basically, just see how far the transformations will go with no risk of losing
Second: name based secret characters. (Examples: toriel from undertale, hornet from hollow night, toy chica from fnaf 2 because I know the freaks that love the overly lewd pizzeria chicken, etc)
Futa mode: basically just gives everyone a cock at the start (different cocks for different secret characters if you're willing to put this much depth into the stuff)
Donut potion and lip expansion potion: puffy anus fetish and hyper lips fetish respectively
Multiboob potion: literally in the name (an extra rack added to the character, 3-4 pairs maximum)
maybe draw the body parts as their own layers instead of doing it all by hand? that would help with future updates as well, since you could just add another phase of growth as its own asset.
