Putting any Flowmaster back there will give you a different sound, but will completely cancel any flow improvement in your exhaust. Flowmasters sound good, but they flow horribly. If you want a "bigger" sound, get rid of both mufflers and resonator, and add 1 muffler of your choice back in for the sound.
And you're right, you removed the muffler. We have 2 mufflers and 1 small resonator right in front of the rear suspension.