From
here. Filed under the 5 Things tag because, well, five things...
1) He regrets that his desire for the military command of Atlantis became public knowledge. It has affected everything that has happened since, from how he is treated within Atlantis (and, yeah, he should have handled it better when Sheppard was turning into a bug, but the marines resented him before that) to, most importantly, how his crew sees him. It makes it look like he is only commander of the Daedalus because he couldn't get what he really wanted and that's not something you can easily brush aside. Even if it's not true.
2) The flight suit is comfortable, okay? Fashion gets forgotten when you spend as much time in hyperspace as he does.
3) After his first cruise with the Daedalus, he contacted an old Navy friend and got a list of book recommendations. Mostly about submarine life, but all about being an officer at sea. They may be in the sky, but that's almost a technicality. He loves his crew, but he understands that this is essentially a job for sailors and not airmen and he's had to figure out a way to teach the qualities of the former without losing the intelligence of the latter.
3b) He also started reading Master & Commander and the rest of the series. He loves the books -- the humor, the way luck and politics and human failing and achievement all play off each other. But they depress him a little, too. Aubrey has Maturin and he's got... Hermiod.
4) He's widowed. Wife died ten years ago of cancer, hasn't really bothered to 'get out and meet someone', as his younger daughter encourages him to do. He's away from home too much, tied up with the ship's needs even when they are in port, and it's just easier to live his life as wedded to the Daedalus and not go through the whole thing again. He's not interested in sympathy or starting a new family or putting in the effort to build again what was destroyed when Maggie died. He's got his ship, his daughters (and eventually, grandchildren), and he's content -- most of the time. The rest of the time is when being around Elizabeth Weir throws him sideways.
5) Sheppard is a better commander than he pretends to be. He's still reckless with his personal safety despite knowing how much that will affect everyone else, but he cares deeply for his men and they will follow him through hell because of it. Steven's not that kind of leader and, as much as he'd like to say that Sheppard only looks good in Atlantis because Lorne is covering his ass six ways to Sunday, he knows that Weir made the right choice when she fought for Sheppard's command.
5b) That doesn't mean that he doesn't think that he can fill in when necessary.