...have never had their full potential reached?
What characters have you always felt COULD be cooler than they are, but for whatever reason, never seemed to make that leap?
For me, one of them was Taskmaster. Now, don't get mad, I haven't read his recent appearances yet, and I hadn't read most of his OLD appearances, either. But something about the guy just screamed potential to me and he's one of the things I miss most about Agent X.