If you're going to the extent of changing to FMIC and angle mount turbos you should've bought an STi.

Keep the Liberty near stock. Nice quiet cat-back system like the HKS Silent Hi-Power and an ECU tweek via reflash for a little more boost and appropriate timing. Wouldn't bother with a stand alone ECU.

Enjoy the Liberty for what it is, a nice comfy GT with a nice usable power band.