An SVT exhaust system would be a good thing. If you wanna build your own, try trubendz.com, their resonated system with Magnaflows is reported to be quite nice. I heard a Zetec with dual Flowmaster 40 Originals that sounded pretty darn good.
If you wanna get creative, you can get a single inlet/dual outlet muffler placed in your resonator location and then pipe clean exhaust from there, no Y and a little less welding.
