1. A Mr. X style enemy that follows you around is a really neat idea but it might not work well with how the rooms and mansion layout are currently designed. The rooms themselves are sometimes a bit on the intricate side, so the player or pursuer might get stuck in a way that's either unfair or too easy. And the mansion layout sometimes doesn't generate many alternate routes, which could result in some impossible situations. I could see this working if there were a floor type dedicated to this mechanic, with plenty of alternate paths and rooms that aren't too busy.
2, 3. I'd love to add more room variety! In general though, I've been using newly added objects/mechanics to guide the design of new rooms, so I'd need to come up with more ideas, and then actually implement them.
4. Eating keys would have to be restricted to the higher difficulty levels, since I could see this being a frustrating mechanic if not done correctly. Also, since enemies and objects despawn when moving between rooms, there's the possibility that the key itself might vanish. Could probably deal with this by adding some persistent data to indicate that the key was stolen in that room. (Edit: also, canonically Nel is object voring the keys, so having a mimic eat the keys would be a bit hard to explain)
5. When it comes to straight up sex stuff, I want to be careful about consent (that, and I don't know if I'm ready to put explicit stuff in my games yet). The pumpkin pred is a funny idea though, and I might just add that to the game.
6. "Golding" wasn't going to be a mechanic originally. It's a thing I put in last minute because the original gimmick (kicking Jack-o-Lanterns causes random effects) had to be cut to make the deadline, but I still needed a good reason for the pumpkins to exist. Having said that, I do think there should be a small extra for golding all the rooms. I might add that along with the random effects in a future update.
While I'd like to do more content updates, I can't make any promises. Right now, Tummy Jam 2 has just started, so all my time and energy will go into making a new game over the next two months. Still, I'm hoping to return to Maw Manor at some point!