OP, I think you are making the right decision. The Tundra 5.7 is a GREAT truck, solid engine, transmission and brakes. The problem is low payload and low truck weight. We bought a 2015 Jayflight 29QBS. I thought we would sneak in under my ratings. With all the extra stuff that the wife wanted, now that we had a bigger trailer, we went over our numbers. I stumbled into my truck, which was used. The heavier truck was more solid, braked better and could carry a LOT more than the Tundra.
I still miss the immediate application of HP from my 5.7 and the tight feeling transmission. My Cummins has more power, but it builds slower in the engine and the transmission has a little more looseness in it.