The "glass transmission" perception is the result of the weaknesses of the '02 and '03 gearboxes breaking under strenuous use. Each year since it's gotten much better, and for '05 and '06 I personally would have no problem doing significant engine mods to a WRX without worrying much about the gearbox.
Nightwalker, since you've already got the 240 toy car, a Legacy GT (preferably wagon
) seems the best choice. Of all the cars being discussed it's the "nicest" and it still has a drivetrain with serious power potential. Just a turbo, exhaust, and EM away from 400 hp. And since power is the least important aspect of the next car for you according to your posts, I would think the Legacy would be your best bet because it excels in all the other areas that we would consider when choosing a car.