Ok first of all you gotta loosen up on the mpg to get extra hp's. The tc will not give you any hp.. actually take away hp if you dyno'd it.

The max hp a tune on a stock vehicle can give is about average 20rwhp + or -. Seen some get about 30 so it depends.

Gears are gonna put more torque to the ground.

E-fans are not gonna be noticeable off the line. The mechanical fan has a clutch on it that is made to slip. So when you first stomp it it slips then catches up with your motor. Stock 05 e-fans pull about 20 amps.. so this puts alternator under heavier load.

And for a cam that gives you low end below 2500rpm... stock cam is about as good as you can get. Sorry. Here is one to look at tho.. it should pick it up some because the intake valve opens up super early. COMP Cams® - Cam Details

Long tubes are gonna really shine in mid rpms and as you go upstairs.

So i'd say SPRAY IT! jk!