In my 7 days of total playtime (90% pvp) I barely noticed the drones in this game, yea you sometimes hear them but you can simply ignore because they're no threat really. Neither do they seem to ever have any impact on game balance, like it's only one time I've seen a drone destroying a weaponcash inside a building, it was pretty cool how it found it's way inside (was on push insurgents hillside).
Now since the insurgents have a serious lack of firepower (still after artillery/rocket buff tbf), I think it's mainly due to the lack of creating chaos. So I had an idea, what about making them come in bigger quantities? Making it a swarm of death. They will scatter and follow anyone in sight, if you don't focus to shoot them down from a distance or find some sort of shelter it will be a certain death. Basically creating the same chaos as choppers do. From now on, the sound alone will induce PTSD hehe