Re: Sheamus more entertaining as the challenger?
The whole thing about Sheamus' Brogue Kick being too week and too low to impact Big Show — who would simply catch his foot in mid-air — was excellent writing.
It came right out of the Orton-Henry feud in which Randy Orton's RKO was set up as being unable to touch Mark Henry on account of his sheer size, and it worked brilliantly to create the tension necessary to carry their matches.
It's necessary to have a heel who appears to have the face's number in some way or another, be it psychological or physicial or both, if you want the audience to really invest in the feud. Because it's no fun knowing that the main face is going to mow down his opposition no matter what.
Vulnerability is the key.
Laying the 314 on your candy ass.