I think one of the powers that Superman has that is regularly overlooked is his Super-Determination. No matter the opponent or situation he is most always able to prevail by putting just that much more into his effort. I know he does it all the time but it's never explicitly stated as Super-Determination. It's like KERS on the F1 cars (which I'm watching right now!) where he holds back most of the time (referenced in the JLU final episode, where he's fighting Darkseid) and uses that reserve when he really needs it.