After playing around and fooling I have noticed that presence of the helicopters mainly is not felt like in real life. I know that some elements are not possible to replicate but the sound should be one of those that could be.
The new sounds that helicopters received are great but their main weak still seems to be their presence in the area. It is not felt from distance and when close other parts of sounds could still be heard.
I know that only sounds of explosions and shooting could overtake the sound of engine and blades.
So my suggestion is to increase their sound, proximity area and add more presense echo and reverb?
This should also apply to jets and planes flying low and doing pass by.