Well, it's been said here enough, but Cap is not Superhuman by benchmarks (the very lowest of Superstrenght is, I think, Spiderman and he can lift, push, drag, etc more that Cap, similar for other physical attributes). It has been said that a persona that's at the same time superior to any one golden-medal-level athlete at their own game is, in a way, superhuman, but when the enemy is lifting cars, you look kind of ordinary.

The super-soldier suerum would rise physical attributes to the top human, which I think is 23 (18 base + 5 from levels). I do not think it would enhance mental attributes, Steve was pretty smart before going through the program and Red Skull was already crazy before the suerum. I have always attribued Steve jump from skinny no-body to super leader to the fact that people are superficial and would not have followed a skinny guy into battle (except for Bucky, God bless that underrated guy).

A good point of reference would be Captain America builds for Mutants and Masterminds 2nd Edition. There should be like a thousand of them around. If there's any designer's notes, that should point you into a good direction.