I will second Maxx. If he's going to be manipulating air, he should need to expend a ridiculous amount of energy to be able to accomplish the things you mentioned in your sheet. Creating a gust strong enough to knock someone down or even to move his own body around would take a lot of energy. Crushing someone to death is, like Maxx said, something you can in no way defend against (well, if you want to nitpick, Lynn could defend against it, but her power lets her defend against most things, so it's not really relevant) and sucking the air out of someone's body is pretty powerful too, especially given that it's basically a one-hit kill against an unconscious person.

He also has no real weaknesses aside from blindness, which he circumvents. He can still cause damage whilst motionless, even if it's more minor-having to move to cause damage isn't really a weakness in my book given that the majority of our characters have to do the same. Too much pressure disorienting him is also kind of an unfair weakness as, at that point, he's probably snapped someone's neck with air pressure, so him being a little dizzy isn't really that big a tradeoff. 

If you're going with air manipulation, I think you either need to scale down what he's capable of or severely increase the drawbacks. It'd be interesting to see you play this as more of a finesse based character rather than someone using raw force: while superpowers don't follow the laws of physics super closely, he would have to expend an insane amount of energy to crush someone with air pressure or send a gust of wind large enough and strong enough to cause internal damage. I'm against the air pressure entirely, but the insane gusts of wind I could see if it was his ace-in-the-hole; his absolute apex. His manipulation of air is a really versatile power (tracking/scents, allows him to deflect any form of toxic gas sent his way, supreme accuracy with firearms if he's good enough, holding his breath presumably indefinitely, etc) and having him be a combat juggernaut as well is too much in my book. If his combative applications were nerfed (he can fire off a hurricane-level gust of wind, but it would take up everything he had), I'd be okay with it, but honestly he's just too strong. Your character could excel in nearly every field (stealth, combat, etc), even over characters who are specialized in those fields. He could easily neutralize Nikki (as no bug is strong enough to endure even a relatively mild surge of wind), for example. If you were looking for a more thematic weakness, maybe there's some problem with his lungs as a result of his power and he has to lug around an oxygen tank wherever he goes to function. That wouldn't balance him out entirely but it would be a step in the right direction.

Honestly, I know you probably didn't intend for it, but I just see too much potential for abuse with this power.