Lucha-Libre is wrestling
Getting Noticed By Management
Uh, I hate to break it to you but Mistico has been rudo before. He turned on Volador Jr. and teamed with his long time rival Averno. But back on topic...
I would book Mistico, Sin Caras, Sin Cara, whatever you want to call him... I'd book him as a successor to Mysterio. I'd have them have a mentor-student type of deal, move to tag titles, then have them lose the belts, lose the rematch, and ultimately have a match between the two of them to retire Mysterio. Mistico moves much better than Rey has EVER moved in his WWE career (and arguably in his career ever) and with a simple masked/mysterious gimmick; I see him getting over REALLY easily with his lucha abilities.
I stand corrected your right buddy about Mistico heel turn. I strongly believe teaming him with Rey would be the best way to introduce him. I'm glad someone here understands how big a Sin Cara vs Mysterio can be for mania 28 in Miami ( big Latino population ). The mask retirement angle can be huge if done properly. And teaming with Rey will help Sin Cara to have more time to learn some English. If they do decide to make him heel I hope is in a Latino stable with Chavo, Primo, Alberto Del Rio , O. Colon lead by Vickie.