If it's not planned in game already, then I'd like to see a quest involving dragon or few leeches (one really powerfull, a kind of really 'BIG boss') as a next strech goal. Epic battle, unique loot at the end. Of course there should be possibility to finish quest without fighting also, but then there wouldn't be a reward in the form of unique treasures, only XP.
And I agree with not having more companions/races/classes, there's already quite much of them planned in game.
My 2c.