Oh ho ho ho. Somehow I think Nick and Puck interaction will be super interesting. I think Jeff being hurt is just...sadly unavoidable at the present and Nick is fairly touchy on the issue of Jeff in the first place, so I think any threatening will end up...explosive, since Nick isn't easily intimidated and resents the idea of someone threatening him.
Puck being on the fence about Blaine shouldn't be too bad but Nick will definitely decide Puck is the enemy if he insults or makes Blaine feel bad. Warbler bros are Warbler bros, after all, and that's serious business.
Let's just say life in their dorm is going to be interesting for a while.