No. A character like that wouldn't really work as a heel. Of course the "I'M THE MIZ.. AND I'M.. AWWWWWEEESOME!!!" catchphrase would definitely get over like crazy but other then that.. I don't know how his character would turn out as a Face.
And I doubt he was a Face last night. They were only cheering him because it was his hometown (or near his city, I don't know nor do I care) + He didn't express his character that much last night to show if he's still a heel or a babyface now.
As a face his character would be a douchebag comedy act, like The Rock, or Chris Jericho, or D-Generation X. The only difference is he would direct his douchey behavior towards heels instead of faces. And actually that's how his character should be, rather than totally neutering him the way they did with R-Truth, John Morrison, MVP, and others who got over as heels only to lose the thing that got them over once they turned face.
Since he's a smaller guy who isn't much of a technical wizard in the ring, he'd be great at playing the underdog in matches and selling for the heel.