Real simple solutions:
To prevent the endless strafing on the ground by planes spawning just to kill troops:
Give the troops weapons that fire

Basically, once troops are actually DOWN, it's suicide to spawn at that field as every troop on the ground will rake you with very accurate small arms fire. Oh yeah, and credit the kills to the Gooney Bird driver

To prevent the enemy from parking on YOUR runway and endlessly killing spawners:
Flak Panzer anyone?
Just put the "motor pool" a short distance away from the field to build in some delay for the FP to get into position.
Once there are vehicles, we'll have a great chance to use all those bomb-laden fighters.
Still, in a perfect world, virtual or not

, the base would have 8 or so troopers defending it. When the agressor troops land they duke it out with the defenders, and since they have better numbers they wipe out the troops, 2 troops survive and they take the base.
These defender troops (1 per building?) also try and take out any agressors parking just to kill spawners. They are 'coded' with really poor aiming algorhythms that only work on stationary and / or large targets; relatively useless against incoming troops and fast flying planes, but great against anyone who's parked.
This also has the advantage of giving bonuses to heaviliy armored ground attack planes. The p-47 was not a great dogfighter, but in this role (immune to small arms fire) it'd be a great ground support vehicle.
Plus, with one assigned to each building, you essentially get an 'easier to capture' bonus the more damaged the base is. For every building that's flattened there's one less troop defending it.
Just an idea.
~Lemur
[This message has been edited by lemur (edited 02-28-2000).]