Don't do the chip until you get some more mods. It will be literally useless. You won't get much more power out of a bolt-on dual exhaust. (reason being is you still have the point of constriction which is what you're removing when you do a dual setup correctly.) Get yourself a CAI to go with your dual exhaust. Check Ebay. There is a constant debate on which is better...a $200 MAC intake or a $50 Ebay intake...I have one off ebay and it works fine.
Try under drive pulleys. Thats your best starter engine mod you can do (unless you add a blower, in which it will be a waste of money). (adds power but also saves you some gas)
3.73 gears with a t-lock. (adds speed no increase in mpg)
Those are the basics. Short shifter won't do anthing but help you shift a little quicker if you're racing...i'd personally do the other mods before that. They will actually add power or accel speed...that wont do much unless you're racing (and btw street racing is banned off this forum FYI)