Making Blast Shield more effective & grenades & such more effective will indeed stop assassin users... i'm up for that. But we're now delving into changing the whole game. People who use Quick Draw will be at a severe dissadvantage, or any other red perk.
Grenade Launchers are okay in my opinion i suppose, but two nades is OP if they're buffed up.
The problem is; some of us want them removed totally, someone of us don't mind them being in the game. There's no winner.
There will always be glitches/ hacks/ beardy kills, cheap shots/ op weapons etc... if the designers took out everything people cliaimed to be OP, we would be getting rid of-
One Man Army
... you all get the point.