My experience with 17x9 wheels with 5" backspacing and the fast ratio pitman arm (w/ apporpriate idler on the opposite side), I had the tire rubbing the rear of the frame rail on full lock. Tires are about 26" tall (275/40 17s) and the car is lowered a bit.
As far as ride, go with a quality shock, I found that to be the biggest difference. I can't really go to a taller tire without changing the fender profile and needing less wheel backspace.