Your post title is "best tow vehicle for our rig" yet you don't post any limitations. Needs to be small with good gas mileage for daily use? Needs to pull our current trailer and maybe something bigger if we decide to upgrade? Budget? New, Used?
More info would give you more educated responses.
I've had a couple of gas 3/4 ton trucks. Bought my first diesel in 2015. Best truck I have ever owned but to small to upgrade trailers. Would by a 1 ton if I could do it over, or when we upgrade it will be a 1 ton, maybe even a dually. We only use the truck to haul our trailers, not a daily drier, and it would be great to get rid of the truck as being the limiting factor.
So best tow vehicle or best with some restrictions?