It seems odd not to consider a control scheme that is so familiar to so many people. Would adding mouse-look break a lot of things?

BTW - this vid seems to show Legend of Grimrock playing with mouse-look: https://youtu.be/xALsxZv0pwg?t=8m53s

BTW 2 - just discovered that cursor keys can rotate. WASD for motion and L/R cursor keys to rotate is waaay better for me.