You have very good points against Cap, and I've noticed all of them at some point or another. Howewer, I must say, I only collected Cap regularly back in the eighties, and back then, he had a great sense of humor, people he cared about, a private life -something I've noticed lacking which has indeed put me off buying his series no matter how praised it's been). Yea, he was completely human and relatable. He can be larger than life when needed, but he can be naive and sensible when well written. And he refuses to acknowledge himself as better or larger than any other individual, no matter how much they gush. Maybe I was just lucky to read him in a good period, but that made him one of the top heroes in my list. And I'm not even american btw.
(Damn, this crappy thing won't accept my lj account!)