Well, the most boring, tedious, repetitive, brain-dead combat I've ever encountered in a videogame was in D:OS.
In singleplayer... fair enough. In coop you can keep swiping/freesing/shocking your coop partner whenever her refuses to follow with your plan. I don't think D:OS1&2 works well outside coop, which is fine. Less so BG which has a strong singleplayer legacy. Still, as some of my favourite games are turn-based I don't think this is where the problem lies, and least not for me.