I'd definitely upgrade the dampers while you're in there, particularly the front. Necessary? Not really, but the car will ride and perform better on the street with a better set of dampers. The PP rears have a lot of compression damping so they can be a little bouncy, but that's largely fixed with a rear shock mount upgrade (BMR's mount also adds back the travel lost by lowering and some).
It's more expensive, but the FP Track damper set, M-18000-F, is worth it. Don't let the 'Track' worry you, there are a large number of folks on Performance or min drop performance springs and those dampers who only street drive their cars. The level of control is much improved over even the PP dampers.
So the ride became less harsh when you upgraded the dampers and kept the SP080?
Yes, it became more compliant. The only other mod I had at the time was the BMR cradle lockout kit (cb005).
I have the Steeda Non-Adjustables. They worked good until I put sway front and rear sway bars. The front still rides really well but the rear became sensitive to bad roads/bumps. I bought a set of Ford Performance track dampers for when I switch my setup again.