Throttle body spacer, high performance plugs, wires, CAI, cat-back exhaust, premium fuel tunes...you can easily spend $2500 on "little" upgrades for your engine. How much performance will you actually see out of those upgrades? 10 HP?
If you shop around, that same $2500 will get you front and rear bumpers, a winch, a skid plate for your evap canister, rock rails, a CB, some recovery gear, and you'll still have money left over for gas. Or it'll get you 33's, sway bar disconnects, some wheel spacers, and a set of flat fenders so that you have room to run those new 33's....and once again, money left over for gas.
Which set of mods sounds like it'll get you further down the trail? Then again, I'm assuming that using your rig off-road is what you're looking to do. I may be wrong.