I wonder if there's a way to make Dominion an asymmetrical gametype.
Lock down blue team in a room with a timed teleporter spawn. Have members of red team spawn in each base/capture point. After enough time has passed for red to cap the points have the teleporter spawn in the blue holding room and move them on to the map proper.
If you can't disable the last stand function of Dominion that would mean that blue team would only have one life until they could successfully take a base. I guess it'd pay to make their spawn room an armory or something - give them a fighting chance.