So I only have 6 Imperial ships so far, all small ships. 3 Fighters, 1 Advanced, 1 Bomber, and 1 Interceptor.
I've tried using all 6 as a swarm a few times, but didn't have the best luck. Mainly because using the cheapest option for them all gets me to 91 points already. That only leaves 9 points to bump up some PS a bit, or put some payloads in the bomber.
Recently I've had decent success with a 5 ship build though.
Howlrunner = 18
Major Rhymer + Advanced Proton Torpedoes + PTL = 35
Saber Squadron Pilot = 21
Obsidian Squadron Pilot = 13
Obsidian Squadron Pilot = 13
Total = 100
It's pretty dependent on a good first attack pass. Idea is that howl gets an attack on a ship and hopefully makes them waste a focus/evade. Then rhymer does his atp attack with ptl and either destroys or heavily damages the target. The remaining 3 then finish off the target if still alive, or attack a second target and hopefully do decent damage with howl's reroll ability.