Thank you for your ideas!
The idea of making higher size levels and intelligence level tied to certain events or unlocks is interesting, it could make it more manageable.
The problem will always be the amount of images needed for each size and the fact that making bigger sizes can lead to big inconsistencies in the characters but I'll think about it.
That "police station" or regulation about the size is interesting but it could feel too restrictive, if I implement something like that it will probably be an automatic limit, more "mystical" like a rule that's just in the area and auto enforces itself.
I have been thinking for a while in a building for special events with more characters but the fact that writing an event with too many characters is harder is stopping me a bit, I may revisit this idea in the future.
Upgrading some buildings would be an interesting mechanic but I'd need to think about how to balance it, using the construction site as nexus for that would give it too much importance so maybe using plain money... I'll think about it, that could give more uses to the money in game.
More clothes are definitely planned, one of them is already teased in game!
I'll keep thinking and developing the game with care (even if I end up missing some bugs until the reports come, sorry for that!).