Pretty flat out there!
The trails you hit... Will you be trying to see how big of a rock you can drive over, or just cruising along?
The Toytec Boss kit is a nice kit. I ran it, but it wasn't able to keep up with the higher speeds I wanted to do off-road, so I upgraded to an Icon setup.
After watching a 5100 (I believe they're used in the ultimate kit) snap on a forest service road going 15mph a couple weeks ago, I'd have a hard time recommending that.
If you want to go fast over the bumpy stuff and have pretty deep pockets, check out some of the 2.5" coilovers and shocks available from Fox, Icon, SAW, King, and Radflo. All great products, but spendy as hell. Sometimes you'll find them used in the classifieds for much better prices here, or on Tacomaworld.
At the top of this forum there is a Lift FAQ that you should read through... Pretty informative.