It could work... somehow. I'd imagine it'd be an extension of a normal game and not the entire focus, as that's somewhat different for Animal Crossing.
As a addition to the main game: Why not? As a whole game with only that one theme:
Wouldn't like it.
I mean, it can be a fun idea and such, but it can be also get boring real quick if you
do all the time the same things and have no variety. So I think it would work better
if it's just a addition to the main game, something like Tortimer's Island but bigger
for example.
That actually sounds like a really cool idea. It could be road trip themed. There would be the usual areas like the town, the city, the island, and then you would be able to travel much more than in previous games. There could be a hotel, a farm, the ocean deep... the possibilities are endless.