I personally prefer one lone thing return, the most...
THE WATER LEVELS!!!!!! The epic music, the epic animal buddies, the epic enemies. Pacing was never a problem with Enguarde (I'm doubting the dev's DKC experience). Oh and, the lack or low amount of bonus levels were nice too.
Well, share opinions and vote away. It could be returning music, characters, etc.
(Idea taken from Donkey Kong Wikia's main page poll, see
http://donkeykong.wikia.com/wiki/Donkey_Kong_Wiki )