Miles, what is done is done, but for what is worth, I Love my Tundra. I never owned a Diesel. But for an all purpose, daily truck with lots of power and then some, Tundras are pretty awesome IMO.
I know folks that pull 31 feet TT and even 5th wheelers with Tundras (though I would not recommend) and are happy with their performance
Dont stress yourself out over that decision, especially if the wife is happy. Dude, you did right! :-)
2005 Jay Flight 27BH
2008 Toyota Tundra Crew Max