I wish I had something more coherent to say than YES, THIS, but... that's basically what my thoughts boil down to. John Sheppard's the rare ace character who sincerely (if awkwardly) values his other relationships; the far more common ace trope is that of the aloof genius who resides so thoroughly in his own brain that needs of the body and heart are irrelevant, and even though that trope's subverted as often as it's played straight, it's so nice to see an alternative presented in John.