Considering the difficulty of finding ten live players willing to commit to the ride, I suggest reducing the number of live players to four for a base capture. Plus, give each participant a base capture score as extra incentive. So, the C-47 pilot or M3 driver and all the live players get the credit. Then let a Jeep carry two live troopers each, so that Jeeps get more action in the game.
I'm not sure how this would work with the normal AI troops. It would be frustrating to be controlling a live trooper, heading for the map room, when another C-47 happens to get there first and drops AI troops. I suppose that might just be the risk you take. I also realize that it would be extremely difficult for the defenders to spot and kill live troopers, considering that they can take cover and use bounding movements rather than just run blindly in a straight line for the map room. But of course, that would be another big incentive for people to use live troops.
I think that the defenders should be able to spawn up to four Jeeps from a point next to the map room, in order to provide a nominal base of fire against the attacking troopers, available more quickly than from the hangar. However, the attackers would have to have at least the M1A1 Thompson or M1 rifle as I don't see the currently modeled 1911 being very effective against Jeeps.