imo the trd pro is a no brainer. You cant get anything but a cloth interior with the TRD off road, and if you want the tow package, premium, with JBL audio on the off road, that is a $4,400 package that requires the orange color(at least, per the toyota website).
For an extra 4k for the Pro, you get internal bypass shocks with springs that are ready to accommodate 33" tires off the lot, an easy clean up synthetic interior seating package, some graphical updates, skid plate, wheels, etc. If you were to update the TRD off road, the suspension components on the aftermarket would set you back probably 2k for comparable lift springs and bypass shocks, and I dont even want to know how much the leather or synthetic seats from toyota or an upholsterer are.
The other alternative is to get the limited, which costs you crawl control and the locker; so that's out.
I dunno. I can see if you were looking at a stripper tacoma to build that the pro is a comparative rip off....but We decided a while back that we like sound/nav upgrades on our trips, and that we would stick with leather or synthetic seating surfaces as we travel with kids because they spill absolutely everything and grind it into the seats, and no amount of shampooing gets it out...to say nothing of the dirt we all pack into the thing on the road for a month at a time etc.....so from my point of view, when considering that in addition to the other features, I can't re-create a TRD pro for less by getting the TRD off road and going to the aftermarket...especially when the suspension that comes on it is adequate for my use.
Just my $.02 as a guy who does the trips with a wife and kids that either like some comfort items or make an absolute mess.