I would suggest a bit of scoundrel, just to have more options dislocate yourself, without having to pass through environmental stuff or better ranger for tactical retreat, this would give you even haste.
The main weakness of the dwarf is in my eyes. Most of his stuff needs armor to be removed, but because you don't have warfare, you get no bonus against armor als you you don't have physical attack skills. Battle stop would be very usefull do clear surfaces as well.
If you would go for rogue a bit, you would have at least some armor penetrating skills (or one). If you lose health, you can still use necromancy to heal your self by penetrating an enemies armor.
Overall the build feels really dependant of the team.
