Characters I liked - and didn't like
I like the film a lot. That said...
Jeff- He was probably the most "likable" of the principles, yet he had his annoying qualities as well. He was likely the smartest, too...yet still clueless.
Pony - OMG, he was completely unlikable and annoying as crap. Whiny, needy, trying to show off in front of the kids he went to school with and clearly never felt equal to, and on top of it all trying to get with the girlfriend of a supposed friend without any remorse at all (and in amazingly pathetic fashion - like without any guts at all). Also, frankly I don't know if he was supposed to come across as someone you just wanna smack, but he sure did.
Tim - He was a vaguely sympathetic and even slightly likable character - even when (in fact especially when) he ranked on the very annoying Pony instead of kissing his ass like everyone else was at first - but then when he pulled the prank on Jeff towards the end he shows himself to be fairly void of much of anything at all. Except misery.
Sooze - Yuck. Unlikable from beginning to end, pretentious despite being talent-less. Then she dumps her boyfriend just because the "rock star" starts trying to get with her. Blech. Go with him and be gone. You deserve each other. Bye.
Buff - Would be likable, but just to stupid to be truly so. Lacks much real depth, even in his "deepest" scene with Beebee. Can't truly dislike him, though since is mostly without any sort of malice whatsoever.
Beebee - I feel like we never really get to know her. Except to feel badly for her.
Erica - Predominantly annoying, without much merit.
Nazeer - He wasn't unlikable and in fact I felt sympathy for him. Couldn't say I felt any great like for him, either. He was (mostly) just there.
All in all, though I really liked the film. Despite not having anyone who was the true protagonist, nor really any clear cut antagonist, the film worked very well. Perhaps not despite it, but (in part) because of it, actually.
But what do I know. I'm just a girl.