I like the idea of keeping the first brisket as simple as possible. Hence, salt, pepper and maybe a little chile powder. I tend to use a probe to check progress, if it goes in like butter, then you are done. And let it rest once you take it off.
As for temps, I do it wrong, so others might want to chime in. You might want to check the Brethren road map for brisket threads, the temps will be there for when you should come out of stall.