How about 1 sentinel in each lighter, just in case?  That would leave 8 of our elite guardsmen in each lighter, and whoever we fit in the Lander... (up to 10 more...) for 2 Sentinels and 26 troops.  If we need the heavy firepower, we might need some right away, after all, and losing just 8 guys for that wouldn't hurt.<br/><br/>I have no idea about the Rules of Engagment stuff... but if you're saying we do it room to room, and sweep our way forward to the Imperial Guard without leaving pockets of resistance behind us?  Yeah, that sounds like a plan.