While I'm thinking of it....
Reading
this on 1/4 2 3, I agree about hoping end game scoring gets worked in and also something more that just a "You win!" screen.
I remember playing beat-em-ups like Tekken or Killer Instinct and they were great because at the end you would watch a little story of what happens after winning. Some were serious, some light-hearted and some comical. I could really see the Troll-kings ending being similar to
Mojukins from Tekken 3 
That could be a bit ambitious so how about something simple like a story? Or even the backstory to the class, kinda like a lesson on the mythos or fiction of the class. Just be sure to include a disclaimer for the Demonologists ending saying "don't try this at home, the in game demonologists are trained professionals".
And if you could link this in with the scoring then you could offer different endings depending on the level of score. A nice incentive to play all the classes.
It would probably be a bit of work so just something to think about.