I've steered away from adding Cooldown based spells to the rebuff modules. Can you think of a good reason to not keep it that way?
Well with combustion at least there is never I time I don't want it up, if cooldown is over then I need reminding of that :)
I will admit that could blood is a little different and I would probably only use it as needed but what about the priest one, I think its called Inner Fire or something. There would never be a time that a priest who used it didn't want it up. I'm sure there must be others as well.