having what you do in the city effecting what happens in the town might also be cool. maybe some kind of a community center, where you can make requests for help, or new villagers, or visits, which would then give your city an animal for a day? it could become an event, with the other animals acknowledging the newcomer, and at the end of the day/when you save, a short cutscene where the animal leaves, and is wished well by the entire town. could be cool, I guess, if the dialog was different, depending on how they're treated. if you treat them well enough, they would move in within a week or so, maybe? NINTENDO MAKE THE IDEAS
All three would be great, they need a permanent Nook'n Go too, maybe Nook's nephews could run it Also, i've said this before, but a Farmer's market could be good.