Re: changing exhaust
I almost immediately removed the resonator when I got my car. The sound is subtle, yet authoritative when the throttle is opened. It's quiet when driven around town at the pace of traffic, so it doesn't sound like you're getting on it when just leaving a light.
Some have complained about drone at highway speeds. I think that's up to your tolerance, but to me it's fine on the freeway
Another alternative is to leave the resonator but get rid of the muffler. Several forum members have done this and have been satisfied with the results.
An added benefit is the ability to hear what the engine is doing. It was so quiet stock that I had a hard time discerning what RPM range I was in without looking at the tach.