Some rabbits DO smell, regardless of a clean cage or not. They have musk glands by the base of their tails. And surprisingly enough, my English Lop doe is the stinkiest of my entire herd. And I mean STINKY! Also, all of my bucks have to stay outside, because I'm allergic to the musk. And some just have stinky pee, no matter what you do. LOL
I agree with correction when he nibbles, I redirect the head and make an ugly noise, and that usually works with mine (they're too lazy to be persistent). You can offer clean (non-sprayed) twigs for chewing, avoid fruits that have a pit or stone, or cedar (which causes respiratory infections in small animals), willow should be given in strict moderation (it contains the stuff that Asprin is made of).
When giving apples, do not give seeds, they contain cyanide. The jury is still out on citrus, I've given it to mine without issue.
Good luck with the super cute buns!