Unfortunately, turbo motors are always quieter by nature. I don't think there are many options outside of a new exhaust.
I've got the same truck, and have been looking for a catback exhaust system. I'm coming out of a GMC Sierra Denali with the 6.2L and really miss the growl. That has been the only downside for me with the Ecoboost, as this thing is a couple steps faster than the Denali ever was.
I'm afraid that its gonna be really easy to make the Eco sound obnoxious, so I have been trying to do my research before pulling trigger. I have been looking at the Corsa Touring system. From what I have found, your not going to get much tone, just more Turbo whistle, which is fine with me. I kinda dig it anyway.