Why Shadowstep+ambush both?
You can just have the other cheapshot + hemo* + kidneyshot for some stunlocking goodness while the other backstab away.

I think it would be fun to run 2 rogues, and if more stealthers are needed, I'd use druids to heals and buffs.

Hmm, maybe 1 rogue (tank) + 4 druid stealth nukers.