Well this is the thing I really liked about the idea. If you don't want to be ordered around, you can simply join a normal squad or stay lone wolf. If you want a special mission, then you can join. In fact, perhaps the commander can scout individual people, like a squad leader can, for the squad. People he knows want to do a mission. And with the squad being disbanded after the mission, its not like a whole round thing. Just a 15 minute mission.
I just love the possible variety. A commander might order a special team to go to the enemy airfield, and prevent them from taking off. Set up a special sniper group over a key area, for area denial. Have a team sneak around an enemy chokepoint, and hide just outside a flag, while the commander keeps the enemy's heads down with arty. Sending a team to assasinate an enemy commander. It really gives a feeling of personal style. And it makes the commander feel like hes going toe to toe with the enemy commander, how it should be.

Futurama: You Can't Prove it Won't Happen