Hi there Notrab, I just picked up a 2010 SR5 this week! I'm in Conroe a bit north of you.
Have you taken some of the smaller routes through Sam Houston National Forest? Always see a line of Jeeps on weekends hanging out there when I'm hunting. After a good rain it can get to be a pretty good challenge through some of the deeper puddles and ruts in the dirt roads.
We also take the ferry over to Bolivar Peninsula and camp out right on the beach, some nice sandy driving down there and it's usually pretty empty depending on the time of year, and your T4R gets to ride on water