First things first. If it ain't broke, don't fix it. That said, I drove a 92 DAK with 318, Doug Thorley Tri-Y headers, Dynomax Cat back, Mopar Performance comp, and Posi Rear. That was a Sport Truck worthy of the mods.
Next I bought an 03 1500 5.7 Quad LB and stuffed Gibson Stainless Short tubes and Flowmaster Cat back and CAI the first month I had her. Kept the CAI but removed the headers and Cat back within days of the install. It just ruined the limo like ride and shattered the peaceful cabin and was NO SPORT TRUCK.
18 years later I'm driving a 2021 2500 6.4 Quad LB Laramie and couldn't be happier with the comfort. Maybe I grew up? Anyway, I read once that these trucks are so smart, all the mods in the world make no difference unless you unleash the computer. The computer (PCM) will limit torque output unless you teach it new tricks. Don't know that to be a fact but I noticed no gain in power in the 03 just more noise. You wanna go fast, buy a Corvette, best speed for the money. JMHO, that's all, your mileage may vary.