Shilo,
I think there is a misconception on your part.  I have yet to find sounds that are missing, that were present before.  
What I have noticed, sounds are grouped and some sounds, like explosions are timed to inject speed of sound (still a bit long if you ask me).
The one sound that I might agree with being missing, is also missing in AH2:  Outside gunfire from sources other than 37 mm belonging to player controlled aircraft or GVs.  -  This I hope can be corrected or I have a setting fubar somewhere on my system.