It never is.
SoR is ideal when a target is going to live for a very short amount of time (think of >5-7sec) and you're going to hit it with a Judgment.
SoC will be better for cleave damage when you have multiple targets in melee range.
Refer to #1.
Depends.
The bombs that have a cast time, don't bother with them.
Those that are instant, use them when you have a free GCD.