The rear exhaust pieces are there to knock down the drone. Removing them is going to increase the drone inside the cabin. The mid-pipe pieces are the “mufflers” of the exhaust. Many folks choose to remove those and keep the resonators on the end, though that’s really more of a V8 exhaust thing.
The true dual aspect of the 3.6L setup is there to squeeze out a few extra HP at redline, but it hurts the overall sound in most people’s opinion, mine included.
Generally speaking, you want more exhaust pulses coming into a muffler to make a pleasing sound coming out. As such, many folks, myself included, have been satisfied abandoning the true dual exhaust on the 3.6L and going to a single DI/DO muffler in the middle and then keeping the dual exhaust coming out the end.
I left the resonators off when I went with my muffler replacement, but I have a different opinion on “drone” than most. There’s nothing saying they couldn’t be kept in place when replacing the two mufflers with a single one, I just haven’t done it on the two v6s I’ve modified.