Sounds like a similar path to what I want to do with my D20. Let us know with the headers and the stage 1s what it does. I also don't think you need the IM until you get to a more serious stage of motor or FI. Nice choices.
05 D20 ZX3:
F2 CAI, Trubendz 2.5 exhaust, Tom's Tune, Eibach Sportlines, black SVT wheels