Arguing "Well he might be better than Blanks!" is a non starter. Lance Blanks isn't the standard we should be hoping for.
Anyone seriously wanting Barkley as the Suns GM strikes me as a bit touched in the head. The guy only mildly follows the NBA for crying out loud (remember, boxing is his favorite sport, not basketball). How many years did you watch him fail at playing "Who he play for?". The guy knows the stars, and the big story lines, but thats about it. I'd be horrified to have him filling out details of trade, consider complex cap room situations, plan long term, et cetera.
What about Charles Barkley ever made anyone think "well here's a real smart guy"? Nothing. He was a great player, and he's got a fun and funny personality, but thats it. At least when Kerr was hired and had no direct qualifications you at least knew he was intelligent and well informed about the league, Barkley is neither.
I mean good God, watch this, you want this guy as your GM? Its not as if he used to not really follow the league and is now taking things seriously, he's just a clown (which is good for TV, not for a GM):
http://www.youtube.com/watch?v=awKP7xjqWPs