Yeah, changing that did wonders for me as well. My mouse wheel has the ability to tilt to either side (I macro this for dodging in other games) and having to click and hold it to pan the camera was bloody awful.
I wish I bothered before rebinding this stuff, because it makes rotating the camera orders of magnitudo more comfortable (and it's something I tend to do often, too, when the game doesn't make it painful).
For a moment playing with this new setup made the controls feel almost bearable... Until I instinctively tried to click and drag to select multiple characters and I remember what game I was playing.
On a side note, I have to say that alternating between this and Wrath of the Righteous makes the contrast even harder to digest.