[@Tachi]

Bluesy: The most dangerous part of any decent explosion is not the explosion itself, the deadly debris it sends flying, or the fire it could create, but the pressure wave that pulses through the air. This wave of pressure the passes through the air can cause brain hemorrhaging and even liquefy organs if one is too close.  

AKA, Bluesy's ability to control the atmosphere around her includes being able to control the pressure of said air. So she can hit people with a serious pressure wave of air, and if their close enough, can do some lethal damage. The pros of this particular type of attack would be that it negates pretty much any physical armor if your hit by it. A US army soldier in a EOD bombsuit can die if he's too close to the explosion, no matter the protection, and this applies here as well. The downside is that it requires to be relatively close and (for balance sake) acts more like a projectile, aka, you can dodge it if you know what to look for. 


As for Walter, yeah I sort of undersold him, but essentially he's kind of an Ironman character: With suit, high tech superhuman badass, without suit, average joe all things considered.