#2. Has Crowd Responsive Catchphrases
If you have great catchphrases that spark reactions and participation from live crowds, you're already ahead of the curve. This is one of the easiest tools to use when attempting to make a transition from heel to babyface. The fans want to feel involved with the stars and this is one way they can.
"Really?" is one that will definitely work the same, regardless of whether Miz is a heel or babyface. The arrogance associated with his "I'm Awesome!" chant is a little more "heelish", but that can be worked around. Fans will happily finish that line even louder once they are fully behind him as a good guy.
I'm not saying that just because he has a couple catchphrases that prompt a reaction from the crowd, he must turn face. Rather, it will make the transition easier if and when he does actually make the turn.