@Simpkin It's like any other control scheme...it will take a few days to adjust if you are used to something different, but I bet if you give it a week you'll feel like it's totally normal. Honestly, i don't know how anyone can play the game and NOT use the Sims 3 camera setting unless they are on a laptop with just a touchpad (then I'd use it too)...the default is so limiting in terms of camera angle.
Left click still can be used to quickly move the camera around, btw. I use it all the time. Not exactly grabbing the screen, but similar results.