No one said DK was smart.
I feel as if Meetra killing the Emperor via a lightsaber throw being a rather...anti climatic ending, I mean sure there have been worse deaths then that but...I mean I just dunno. Speaking of that, wouldn't killing the Emperor stopped his attack anyway thus saving Revan aswell and killing the Emperor? Just throwing that out there.
Darth Nihilus wins this alone. The Emperor is just another tasty treat.