I've +1'd this wish before, but I think the best you can do currently is ".vsquelch all"... I think you can do that right? Than then unsquelch your squaddies. Sounds like a pain, I know.
If anything, I wouldn't mind having a volume toggle on Range VOX. Essentially working the same way as Zoom Toggle, you adjust two different preferred volumes of the Range channel and toggle between them as you wish. But that still doesn't solve the way VOX transmissions can get clogged up and you can hear a check-six from your wingman 4 seconds late sometimes.
If you value communication at all you've got to get TS or Vent, imo. I have my in-game voice volume turned down a little bit and my TS cranked up, I can mute TS for a second if I really need to hear someone on VOX, but that's never the case.