I hope there is more than 1 character model for each type. Seems like that would get visually stale quickly.
Every class has extensive customization for colors,emblems,symbols and tattoos.
Also you get more and more equipment that looks different and can be mixed and matched and even "transmogrified" so you can use the stats of one armor but the look of another.
You'l easily be able to make a knight that looks different to others.
Helmets especially make a large difference in looks.
I had a fully masked chain helmet for my Raider which looked vastly different to the standard helm.
Ok, this gameplay right here is actually pretty decent in many places https://www.youtube.com/watch?v=DsVLKBRP92Q
They actually block sometimes and get some proper fights in.