Class Quests Should Be Required.

[Kurando]

You could add all those requirements and more OP, but players would still find a way to not use them. Regen spammers, Ice mages, mute bards etc, whatever it is it can fall under difference of playstyle; so people will do what they want. If it's really that bad that a duty run is under threat of not being completed, consider kicking the player(s) or just grit your teeth and get through it, you'll only see it again.

[Vickii]

I wouldn’t just spam Regen but I don’t think they should be lumped in with the ice mages and mute bards. It’s a key healing tool for WHM, especially at lower levels.