There doesn't need to be more weapons, but more rebels/troopers. Just because the Emperor says he has assembled his best fleet of troops doesn't mean that it is one fleet. He could of meant his best fleet and hundreds more troopers. You could give the best fleet a red stripe on them like the ones from ROTS and have them be the last ones standing, then have the others normal.

You could even change Palps line to "I have sent all my troops" instead of "I have sent my best fleet." I'd like to see overview shots of Endor to make the battle look larger. That would help alot.