Your initial list looks comprehensive and reminds me of my first mods.
On fuel economy forget it, you will lose a few miles per gallon especially if you go to a 3.25 inch SC pulley. You don't need an intercooler running a 3.25 pulley, however, later on it would be wise to go to a larger throttle body. It will help cool and improve the intake charge. IMO the 3.4 pulley is better for the street and overall driveability.
Finally, I would recommend a hi-flow CAT and the DHP PCM has programming provisions/maps to take advantage of exhaust mods. Also go with a u-bend delete. A Catback exhaust system is probably a waste of money for the hp gain but it will sound great. Good luck!
Thrasher CAI, DHP v1.0 PCM, SLP Headers,
3.25 SC pulley, CAIT GMAF, 2.5 DP/Hi-Flow CAT,
u-bend delete, 160 TS, ZZP Stage 1 72mm TB,
TB spacer, MSD 8.5mm wires, Autolite 104s,
Goodyear Gatorback Serp. & SC Belt,
Nitto NT555R Drag Radials