Couple of things really, and this really is just a wishlist.
One thing that's been bugging me lately is that if there's no airfield on a landlocked map then I can't use ALiVE for airstrikes. It would be awesome if there was a virtual airstrike option. I know there's always been a push to avoid virtual supports, but I just think given the size of a lot of maps, virtual would be a good option to simulate coalition air forces on standby.
Rolling in Spyders civilian interaction system, or coming up with something similar for that increased immersion. Nothing like being told certain civilians are up to no good. I know the devs looked at persisting civilian names and struck issues, but something like that would be amazing. Making the civilians seem more "alive"
IED's could use some love. The EOD mod promised so much but never actually delivered anything that wasn't a buggy mess. I'd really like to see actual dickers watching over IED's they've planted, maybe IED making materials in a house/compound which could work in with the civilians being up to no good, more IED objects like gas canisters etc.
Now this one's really pie in the sky and a ton of work no doubt, but it would be awesome if ALiVE detected ACE running and replaced all the addactions with ACE interactions. The scroll wheel interaction system needs to die.
A couple of things I've picked up playing BTC Hearts and Minds missions:
An interpreter role/s- These are set by the mission maker and only players with this role can get information from civilians, simulating lack of knowledge in the local dialect.
OPFOR UAV's - In the H&M missions the OPFOR will use the cargo drones and drop grenades from them, similar to the way ISIS have been using drones to drop 40mm grenades.
I also really like this one side mission in the H&M mission where you have to go and do medical on an injured civilian, although that's only really fun if you play with ACE advanced medical.
One final thing, and I have no idea how this couple be implemented, but it would be amazing if the enemy ran supply convoys (especially for the non insurgency missions) that could be disrupted. I just really like the idea of doing recon to find a convoy route and setting up an ambush/calling in a strike to take the convoy out, and for it to actually affect the war somehow.
Oh and just to back up @Cobra I also preferred having to blow up installations instead of the hold action. It was often fun to just drop a JDAM on target buildings :)