Thats an aweful lot of work and a nice car to just give up on. I know man, I felt almost the same way a month ago, but my car was really broken.
An intercooler is something you can save up for slowly and isn't going to cost you to install it.

How goes the idle thing? I have mine working good now that the min. pulsewidth setting is down, I replaced the front bank O2 sensor, fixed the faulty MAF electronics and used my emanage to lean out the MAF curve a little more.

What I'm driving at is that it is just a series of steps you have to follow before you reach automotive Bliss!
I'm just about there right now, so will you with a little more patience and a few little mods.

Tom

Former owner of '99 CSVT - Silver #222/2760 356/334 wHP/TQ at 10psi on pump gas! See My Mods '05 Volvo S40 Turbo 5 AWD with 6spd, Passion Red '06 Mazda5 Touring, 5spd,MTX, Black