That's why I suggested having a big troop approach sequence (while the Rebels are in the bunker) showing them marching and flying in to take out the small band of Rebels, seen from many angles, so the audience thinks,"How the hell are they going to get out of this one?"
The assembled troops we see in the current versions are about the amount of troops you'd expect to be there anyway, not the entire Legion that Palpatine boasts about.