ive seen the car in person...and i am totally in love with it, aside from it being Auto
i say your next mods should be LSD and struts, and a HEADER!!!! im getting way ahead of you dude with my struts/springs/sway bar/strut brace/intake/exhaust and soon header LOL j/k! but i agree...finish the suspension, find a nice LSD (infinity J30 viscous LSD's work i hear...) and get a header...then save up for the 5 speed swap!!!! thats what i would do...but youre not me either
ill call you when the header gets here, and when it goes in...i think, if it sounds as good as i hope it will, and performs just as well, then it will convince you
ps...get NGKs!!! not sure what the 240 KA's run, but im running BKR6e-11 copper plugs, one heat range colder than stock...gapped to .047, and it performs really well. im sure youll be happier with them than the Bosch's. you gotta chang them more often, but its worth it (the NGK coppers run better than the NGK platinums IMO).