This has been discussed before, and I like the idea.

My idea in the other thread was to have specific troops to help with a certain task. Commandos to destroy auto ack/manned ack. Engineers to destroy ordnance bunkers and fuel tanks. Regular infantry to take out barracks and capture a town.
They'd be used very similar to the troops that we currently have, but instead of running to the map room/command bunker, they would run to the nearest target(s). For instance, let say that "commandos" are chosen and all they can do is destroy auto ack. Once they are released from the troops carrier they run to the nearest auto ack and destroy it unless they are destroyed by an enemy player. Lets say that it would take 3 troops to reach the auto-ack gun to destroy it. Once they reach the gun *puuf* they are done. These special troops would be immune to the auto ack.
Stop and think about the possibilities of this. There could be commandos for auto ack, engineers for ammo bunkers and fuel tanks, infantry for capture and barracks, etc etc. The other possibility would be to have base launched engineers to repair those items that were destroyed by enemy infantry. Snowball it. I could see a field being rushed by infantry and out from the hanger pulls a tank of 2 for defense and all they use are the MG's vs the hordes of Soviet SMG infantry. LOL!

This could get fun real quick.