Keep us posted on the tune! I am also looking at diablew and the blackbear. My Range AFM delete likes to turn off randomly, but its never thrown a code. I really want to see what eliminating the torque management and changing shift points will do for the truck.
I know I'm late to the party, but just thought I'd share my experiences.
I would spend twice what I spent on quality shocks. Completely changes the feel of the truck, both on and off road. I can't say enough good things about my kings, and a buddy of mine has Fox 2.5 on his 2016 GMC. He agrees. Anybody weighing the added cost, should just wait and save. It's only money, lol
I have the Magnaflow kit on my truck, with the airraid intake tube. Sound was a little loud for me, so I had a buddy weld in a shorty high flow resonator. Now the truck sounds great, but there is no noticeable drone on the highway. I would assume any flow-through 14" muffler kit would be very similar. I did the intake tube first, and was surprised how much just that made a difference in sound. You might consider just having a muffler shop cut the flapper and stock muffler out, and replacing it with a flow through muffler of your choice.