For question 3), what would a better rotation look like to you? Such as using Life Surge for full thrust, and including more skills that don't stop the GCD combo rotation. Exp: Would be weaving in spineshatter as you said it's better to get the damage from it.

As for the True North, a useful situation I could use it would be if I know the boss is going to do an AoE attack that my positional would cause me to get hit by, I could True North instead to keep doing damage, get the positional benefit, and not get hit by unneeded damage. If that makes sense.