I think the offset of your front wheels is what threw me off. They are under the car a little more than the rears, and the rears are wider as you mentioned. Did you notice any deterioration in the ride quality? I think the new car handles lowering much better without spoiling the ride. I rode in srichard's car with the 19" Drift Rs and it was still very nice and smooth.
Ride quality is still really good - friends who've ridden in the car said they were surprised how nice the ride is, and that's before I told them I had lowered it. It has just a little bounce, but it's firm enough that I wouldn't want stiffer shocks. I'm really happy with it.
20" wheels are perfect. I run them with a 35 sidewall up front and a 30 in the rear and the car doesnt ride any rougher than with the Eibach Pro kit. The car handles like its on rails. I highly recommend them.