I found that the Zerosports suspension was plenty stiff enough. On the track, just turn the dampers up to maximum. The car is roll free, and steers neutral with a tendency to oversteer. I didn't see the need to upgrade the swaybars.
Other things that made a huge difference on my V7:
Antilift kit (no more front end lifting under hard acceletation)
Intercept type EBC (reduced spool by ~400 RPM, could hold 1.6bar to redline instead of dropping to 1.0bar)
Bridgestone RE070 tires (much better turn in, steering feel, grip, but noise and ride quality suffered)
The Walbro is a good idea, and you're lucky that your factory ECU is reflashable.
I'd say you're looking at >230kw after a good tune, with a nice spread of torque and good handling. It'd be great as a daily. If you go much further, you risk stepping over that line and making compromises in your DD for the sake of speed on the track.