I'm not too happy about the deathknight either. I'm not happy about the idea of having to control 2 characters at the same time, that sounds quite stressful. I hope their next Divinity game after BD won't be a RTS (that was a JOKE, so shut up).
I have faith in the Larians (I think they will probably make it work), but I'll definitely not buy it without playing the demo first.