Personally, I wouldn't touch the suspension.
Just a small change in the the tires side wall can make a BIG change in the way the car rides.
If I was going to change the wheels anyway, I'd probably use a 45 or even a 50 series tire, as wide as would fit in the wheel well without rubbing, and go with a slightly taller tire.
I'm glad I'm OK with the way my "stock" 04 rides and handles, but I wouldn't mind saving money on different size tires. Good Luck.