I loved almost all the kingdoms in the game, and there wasn't a single "bad" one in the game, imo.
The one with dragon bossfight was my favorite, even if it was lie a single corridor. Felt very alien in Mario game.
Seaside with those capturable fish things that you can fly around with were pretty awesome as well. Liked the one with the snowy blizzard as well.
Bet with Intrinsic:
The Switch will outsell 3DS (based on VGchartz numbers), according to me, while Intrinsic thinks the opposite will hold true. One month avatar control for the loser's avatar.