Actually, the way the Sentry is working right now, is he doesn't do pretty much ANYTHING without being told. Even killing, which he seems to still have an odd on again/off again aversion to. He's shown to kill pretty easily in the past, then we find out a lot of his enemies are actually just residing in the Negative Zone where he put them, then we find him actually questioning killing.
At first, I really -did- enjoy the Sentry, because I really liked the idea of a guy just so powerful, yet so restricted by his massive chemical and psychological imbalances, and unknowingly/unintentionally creates his own greatest enemy. His story was great in the fact, that he arises to the level of what every hero should aspire to, and gives his entire life up to stop this great threat to humanity. Then the entire scope of the Sentry is pretty much lost since his inception back into Marvel past New Avengers (where he used very little of his power, as to prevent a Void emergence).
Then it was explained the Void ALWAYS comes out when the Sentry does, which is cool, but apparently only to balance things (which isn't. I liked the idea that the Void really was his own man. And it's only fair to say the Void doesn't always follow these rules, but is now just Sentry centric, where before he was just doing his own thing).
However, I'm definitely not liking the entire, "Yes, you're the master of the Void, you use him, and don't at the same time, and you're in control," deal he's got going. It takes away a lot of what made the Sentry great. That, and the blubbering, "I r did gud, mistur Osborne?"