If you plan on increasing power at all, look at getting a stronger clutch. I have a '14 6.7 with RaceMe tuner (wanted to be able to revert to stock with more covertness for warranty) and with even the 30HP tune I can slip the clutch.... with less than 30k on the clock. No experience with other tuners, but it was stupid simple to unlock, delete, tune. Franz is working on updating his instructions to be a bit clearer as well. I've heard good things about the EFI Live crew. On the raceme there is a lot of TQM below 1500 rpm which can be corrected with custom tuning (saves your factory clutch from eating itself, but it's still a matter of time).
I have a 5" turbo back on and get no drone except under heavy load in the mountains when towing. Not sure what everyone says the drone is, it's louder than stock, sure. But until you've had a straight piped 6.0 with stacks, you don't know what drone is. LOL.
Out of all the emissions stuff, the CCV is the only thing I believe actually makes a difference. The gasses that get reburned from it are really really really bad stuff, but that is up to you to decide.
So far I've just unplugged the egr/throttle valve and have the 5" turbo back. The easier it is to be back in warranty compliance the better. And WOW did the truck wake up. Drove it about 1000 miles stock before doing all the changes. Can honestly say that on the highway at 75mph I am getting a hand calc'd 25mpg. Stock I had gotten 22mpg in the same conditions.
'14 2500 Laramie 4x4 G56, RaceMe Tuned, 5" TBE, 2Low, BD Power Steering Brace, SB Street Dual Disc, GN & Tow Package, RAX WifiConnect Upcoming Mods: undercoating, 4-corner air ride (source TBD), larger inverter, more air and fuel, lighting upgrades