+1 on the key driver chip. This would be your quickest way to quote "tune" your car. Although they require your ecu to be socketed and this is sometimes hard to find / and or expencive.
If i was in your position i would do the following - get a plx wide band ( if your serious about moding on your dsm a wideband is 100% needed. these cost about 200 on extremepsi.com ) Then go on ebay or craigs list and find yourself an safc, or safc 2. the price really dropped on these since the safc neo came out. I had the key driver chip for about a year and although i did like it alot, it required some tweaking with my safc to run properly. What ive found over the years is the quick-fix is usually not worth it. The time you spend buying and installing a cheep alternative to a problem only comes back to haunt you. Take your time and save up for the correct setup youll be happier in the end