Actually i would put Clockwork as Sly's enemy or Neyla from Sly 2
Parappa/Colonel Noodle (Before he turns good in Parappa the rapper 2)
Sackboy / A evil Sackbot (Since i don't really think there's a main enemy for LBP i think a evil Sackbot would be cool)
Nate/Harry Flynn/Zoran Lazarevic. (Because both of them are better when they are together)
How could I forget about Clockwork! But did you forget the fact that Clockwork is gigantic?
Flynn and Lazarevic don't really get along, Flynn really annoys Zoran...
Yeah i remember But i would rather have Harry. He may have been a backstabbing piece of crap but he was funny...like when he greets Sully when they meet out in that forest. Again i would actually go with Neyla instead. She is able to do most of the stuff Sly can do as seen in Sly 2 but she can trick people into trusting her and has a whip.