Currently I train only defense players.
SB monsters with ID, RB and PA. In Utopia I have three such players, the fourth one is more balanced.
In my defense training, it is more approach b).
I train SB until a certain point, than switch to the next skill. Sub training (not elastic effect!) is an important point too.
SB trains RB and ID, RB trains ID. So if you are lucky, you get most of the needed ups for ID through SB and RB.
You have to check for the offensive build, which sub trainings help you.