Amazing! Well Done! I’m very ready to stop the break and play the GD playthrough again and then keep on build creating 
Though there seems to be an order of class names; I hope it will be like this;
Soldier - Berserker = Thane or Reaver, both fitting acording to the meaning. Reaver means like a barbarian who takes booty after a war and Thane is like a warrior who rewarded land after a war by his king. Dreadnaught is also very fitting.
Demo - Berserker = Mystic.
Occultist - Berserker = Zealot.
Nightblade - Berserker = Veilwalker.
Arcanist - Berserker = Evoker.
Shaman - Berserker = Primalist.
Inquisitor - Berserker = Runekeeper. (This one could be more creative like Doomster or Doomsdayer since the Inquisitors are some kind of judges. Since Berserkers, Runes and Ravens are part of the norse mythology, ‘‘Forseti’’ is an another option. Runeraver is also better than keeper because Berserkers aren’t keepers.
Necro - Berserker = Dreadnaught. Apparently it means ‘‘The strongest of it’s kind.’’ But have you think about ‘‘Draugr’’?
Oathkeeper - Berserker = Thane. But not satisfying. I think it should be about blood and feuds. Avenger might be a thing though there is a set but you get the idea.