I think RIGHT NOW, the biggest face reactions go to Undertaker and Eddie Guerrero. So then you have to look between the two guys and realize that Taker couldn't quite cut it as a top face anymore probably because he really can't and more importantly SHOULDN'T talk on the mic. It adds to his aura, and his intensity. Eddie, however, is mainly on the mic. It's a big part of his run.
I'd go with Guerrero, personally, because I think he's the only one in the right spot to be the biggest face. HBK is getting old, none of the heels could possibly deliver in that position, Benoit's ring-work just can't make enough face pops, and Jericho is the man, but the WWE refuses to push him correctly, which brings us full circle.
Or you could just go with JBL

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