Don't really see an improvement on Jacqui she's still just as average.

Notable Things: Has some Bruce Irving stuff from Tekken, Has Jax's Dash Punch

So I'm reminded of two better characters than her, grand.

I always thought Nightwolf would be the first character to get an in-fight Animality. But it looks good on Kotal too.

Yes, but I think it is just for trailer purposes. Atleast I hope it is. Maybe they just want to suggest there are stage transitions but don't want to show us how they would go. Or maybe it is something Kronika time-bending related. Who knows. Can only guess now.
The first part of the trailer is the arena of the Kollesium and the second part seems to be one floor lower. The large cage in the background seems to be the "pit" in the arena.

To be honest.. I liked Jacqui's gameplay way more than Cassie's. I really gonna try Jacqui and I am sure I have a good time with her. Her Fatal Blow is one of the best in game. So I can't wait to get my hands on her (in game, guys).

Yeah Kotal. Looked like pure fun. Finally you can do more nasty things with him and play more tactical with his totems. Right now it seems my favorite Kharacters to play with are: Baraka, Jacqui and Kotal. I also like to play some grappler. I think Kano could be a great choice but maybe they reveal more grappler like Jax(?). Would be funny to see The kollector as a grappler :D