I understand completely.. a proper tune, no matter the mileage, will add more power than intake, exhaust, and e fans put together...
I will be getting a tune on mine and by that time i will have 200+k on the truck. a tune will dial in your shift points, power curves, and general power gains all around.. this can be done without any mods.. but if you do mods , you will need a retune.
but if you want noticeable power gains without spending 2 k, a tune is your path.
but with 180k+, I would buy a quart of Kanolabs Kreen, and give your moving engine parts a GOOD scrubbing... maybe new plugs too after you are done doing that. you see see alot of stuff come out of your drain when you use this stuff, it works!!!
intake will help pedal lag and response time but might only give you 1 hp.. it will give a nice tone to the motor that wasn't there before.
clean throttle body, clean Maf, drop in filter, intake.. all aids in air flow.. new plugs will detonate fuel cleanly, maybe evem change fuel filter.. if you do all these mods, it will cost less than 300 bucks and help alot, not in hp but in happy motor. lol
I would spend the tune money on nice rear shocks with air canister reservoirs so I could pump and deflate accordingly...