His lack of Superhero Powers...
I always felt they underutilized his superhero capabilities.Rarely would Clark Kent "turn" into Superman. I don't want to watch an entire episode of Clark flirting or trying to develop his love connection with Lois. Yes, I know it's character building, but the majority of the time he'd only use his powers if it involved saving/protectin Lois, not the universe as a whole.
And even when he did use his powers it was only for a brief moment at that.