I suggest allowing the Jeep to tow.........
1. A mannable flak cannon. Serious lack of mannable FLAK (not ack) guns at airfields. Cannon cannot be fired when in tow, takes about 10sec to detach and then can be fired by someone who has joined the player, or by the player himself (position 3 etc.) like in the bombers. Difference would be that if the player himself mans the flak the Jeep stands still near it.
2. Mobile artillery cannon, similar setup to the flak cannon (10 sec detach to fire etc.) but with the manual, land and sea gun modes available to ship guns and shore batteries. Also if the player detaches the artillery gun, and stays in driver position and drives around then he can use the gun to call in an artillery barrage. He can use the "click on the map" method to call in the initial spotting rounds and then type in corrections, (e.g. .fire 20N 50W) etc. and then when hes happy with where the spotting round lands, he can call in a barrage (a additional key map perhaps?) which will bring down 20 or so HE rounds in a closely packed group (one after the other).......
Both Jeep and the cannon can be destroyed easily (20mms) if Jeep gets killed the player automatically goes to the cannon(s) and vice versa.
Just my 2 cents......