You can make one of those work, you know. You just have to figure out how to make Alpha play a part mostly seperate from yet involved with the rest of it. Maybe you're supposed to defend just one cruiser or something, and everything else has other escort wings.
My personal solution is to have Alpha knock out the enemy command ship's weapons subsystem or comms. If the weapons subsystem, it was coordinating fire-control for the enemy fleet, and now quite a few of their ships are having trouble hitting the broad side of a barn.
If it was the comms, which is harder to FRED but ultimately cooler-looking, the enemy fleet goes bonkers without their commander. So they start manuvering around and attacking apparently at random, and this is not a good thing for their chances of winning.