Jack,
As for the bearings, you can just get them repacked with grease if you haven't done that service before. I don' think the bearings need to be replaced unless you have excessive play up there and have never done a repack. I know there is a thread somewhere that points to another Isuzu site with a step-by-step for the bearing repack.
R1 Concepts rotors and stock pads are working good for me, but if your stock rotors are not warped or grooved, you may consider keeping them. A brake shop might just resurface them if they are still good.
I am going to leave my CV boots alone until I have to replace them. I agree that they should just be left alone unless there is a problem.
I am thinking about the brake line upgrade as well, next time I do my brakes.
Bart