I can always win this level, as either Imps or Rebs, in Conquest, storyline or Instant, with nothing more than a basic Trooper. But then again, I have mad skillz :P
As Imps - Spawn at your Box, run down to the middle (shouting "follow me" because your AI buddies are just that dumb), capture the Arena. Stand next to a medbot and face the Rebel box, SHOOT ANY SNIPERS before they get you, then run out either the side or the front, whichever has the most Rebels coming through. Shoot them all. Then go to the other place they're coming from and shoot them all. I usually run down the corridor toward their far base, lob a grenade blindly up the stairs, then turn around and head back to the middle. Run up the slope toward their Box, gathering followers when possible, and take their Box. You may lose the Arena in the meantime, but no biggie. Once you have both Boxes, you control the Arena. Push out toward thier last CP (Gate?) and mow 'em down.
As Rebs - same thing, mirror image. Take and defend the Arena, then take their Box. It takes a few tries but you'll eventually get it.
As either side, it helps if you move to the area just under their Box and lob a few grenades up there. Try not to hit the bots in back though, you may need them yourself.
Frankly, the other Yavin map is tougher and swingier than this one.