So, is that a dagger? (In the new concept art.)

[Cerat]

2 others in cloth. 1 definitely a caster, the other equipped with what could easily be a cudgel.

There is no evidence to suggest that it is really caster gear for the "dagger" wielder, nor the fact that it is a cudgel. Looking at it, the way the shadows fall along it and the way that it's overall designed and held, there is a blade running along the outside edge of it, closest to the edge of the drawing, and the rest of it is flattened and not rounded out like a cudgel would be. It would be taking more of a cylindrical shape overall, which there is no graphic support for such.

That being said, the character is DEFINITELY wearing light armor gear, but due to the fact that the vast majority (if not all of) the gear shown in that art is gear not currently in the game, it's all speculation.