You want Ebon Hawk first, Slave 1 next and IG third then prob empire bomber but almost never called so in GAC if using elsewhere don't even bother (it is rare 3rd reinforcement is ever needed anyway, ult almost always happens before that). Keep the chaff going.
Opponent (AI) always seems to call slave 1 first which for the most part removes RNG if you are decently matched. They also then use first special regardless of target locks.
On other matter, make sure your XB is a tad faster than RC. You need XB to call RC to get mark where you want (debatable but I think RC better).