Taylor, this is damn near a shoe in the for best game in this category of games already, and it's only getting better with every update.
Now this may be complete wishful thinking on my part, but I was thinking about ways to increase the prevalence of stuckage in the game (Because, y'know, stuckage is hot). I was thinnking maybe something like, as a character's weight increases, either player or NPC, in certain places in the game there is a chance for them to get stuck. I was thinking maybe a character could get stuck in for example a seat if you go to the cinema, a booth if you go to a restaurant or cafe, maybe even some doors at really big sizes!
And then it would be awesome enough as just a message that comes up and you continue on, but it could even be made into a little minigame where you have to decide what to do and your choices determine how successful or unsuccessful you or the NPC are at becoming unstuck, or something like that.
Now of course, I'm no game developer, so I have precisely no idea how easy or difficult this would be. But you seem to be a very talented developer, if this game is anything to go by, so I'm sure if you wanted it to you'd be able to absolutely nail this as a new mechanic/minigame!
Anyway, I hope my suggestion is well received, and no matter what you'll always be able to find me playing this incredible game!