Was getting 17 MPG stock for first 1000 miles and then added level and 35x12.50 and now down to 15 MPG. Have MT and E rated tires, but only drive 10-15k miles a year so def aesthetic decision.
Looks great, but any modification will impact a vs stock drive comparison. Like others mentioned, what your main use is and willingness to lose a little comfort level are, everyone is different.
I don’t regret lift/tires, but would be lying to say it feels like a stock truck. Best of luck with decision and congrats on your new ride!
PS Added pics of stock vs level/35s side by side to compare the two