Wotcha and welcome - if you have addressed the exhaust flow look at hi flow filters for the air on the way in then get it mapped to suit.
from then its looking at increased fuel supply, FMIC, larger turbo, uprated internals, flowed heads, uprated clutch, brakes and chassis components (bushes ARBs etc) and cooling system.
You could look at the handling side first and increase power to weight ratio by lowering the weight sorting brakes and suspension then with the same power you could be moving a lot quicker?