Tein Super Street Coilovers are on the list, should fill up those archs a little better.

Others on the wise list are....

AVO450 Turbo
APS750 FMIC
High flow injectors
Fuel Pump
Pioneer Double Din DVD (going in soon)
Maybe a sound system to match
And maybe spend abit of cash on the cosmetic side of things in the engine bay, neaten it up abit, have it all match.