Is he such a key character that if he ever got zombied/killed off, that the series would come crashing to a halt?
I see him as being like Alan Alda was in mash, carol oconner in All in thge Family, as the focal point the show is built upon, and so when they moved on, the show would just die off with them!
Personally, I don't think so. I don't really care for the character or actor. I could easily follow most of the other major good guys.
However, it seems that this whole thing is his story.