I've seen it said before that FoF gets its value from being switched into/out of for the other stances, and I can see that in some small way.
As far as your recommendation for Meditation, I think making it possible to use in combat is probably a good idea as well. I think if they were to make it its own oGCD with a cooldown, people would complain about how they either have to macro it into all their skills, or constantly stare at a short cooldown... Whereas if they were to make it stack at the end of a combo finisher, it would be pretty much the exact same thing that WAR already gets with Wrath.
Maybe tie it to something like critical hits. Every critical hit grants a stack of Chakra, and at like 15 stacks of Chakra you get a noticeable aura effect and can then use either Purification or Forbidden Chakra. It flows with the playstyle, doesn't work exactly like WAR, and allows both skills to be used in combat. It also makes it hard to get prepped pre-combat, so it loses its status as a powerful opener, and then can remain at the current potency without needing to be nerfed.
EDIT: Also, I really hate this stupid forum system that limits the size of replies and forces me to edit everytime I want to post something other than "LOL".