Don't read too much into reading the gauges in most newer cars. Those gauges are stabilized. If the temperature is close to normal, they read normal. The temperature has to change a whole lot for the needle to move at all.
I don't know about the new V6 but the V8 as installed in the 4Runner is just about bullet proof. There is no need to engineer anything in the way of changes to the oil or cooling system.
If you are looking for a little cushion for the cooling system try a bottle of Red Line's WaterWetter. It's simple, just lower the coolant level just a little bit and pour it in. Look for more info at Redline.com. We've used it in severe applications and it works just like advertised.