I LOVE the sound of grenades and blowing heartbeat sensors, but the rest of the firing lacks a bit of expressiveness imo. I mean the airstrike is really not impressive and the artillery misses that strident sound of the shell splitting through air as it comes down. Would be nice if this sound was added, and that the cadence of firing of the artillery was a bit random, because right now it’s too regular I find.
This is a question of taste, I know … but I would really like that the firing sounds feel louder, deeper (not Johnny) with more bass presence, because right now I feel a bit like these guys :
I’d like the machine gun to saturate my speakers 
For artillery, maybe somethink a bit like this, but more high pitch incoming death sound ? I love the air sound, but not the explosion sound in this video though … (best one at 0:34)
or more like this ?