I'm pretty sure you are safe with 215/40/17 or 18 on the front and 235 on the rear, but sure someone else will confirm, I think the offset is around 32/34 with the compo's.
As for shocks, if you want a nice comfy ride with really well controlled damping then koni adjusties are ace, especially with chassis dynamic std ride height springs, these only drop around 3/4" to 1 1/4", when used myself.
tabetha