JOE#P1

I own a P1 with prodrive 18" alloys and its now time to change the tyres.I've been running on goodyear F1's size 225/35/18 but I find the ride very hard and alot of space under the wheel arch.I thought of putting the same size back on and putting up with the bumps and lowering the car but I dont really want to change the standard springs.Shall I run fatter tyres if so what size and what's the ride and handling like.