Suggestion I have - make the thighs grow when using the bottom potion. It's a little jarring when a character has wide hips and a huge dumpy, but the thighs are petite/normal size.
Also, I think it could be neat to be able to influence the traders. They don't need to have requests, just the ability to give them potions to morph them however we'd like, whether giving them an even bigger cake or a big belly.