Shattered Kingdoms

Since advocates are stating it's simply an aesthetics thing, make it just that.

Casters can still type sleep, but instead of saying 'John is sleeping here' it would say 'John is here in tranquil meditation' or for relgions 'here in meditation to Lord Dulrik' or whatever...they can't see, hear, just like sleep. All regens stay the same.

This works too for non-casters, since the mana and hp regen rates stay the same. No need to sleep and meditate, non-casters just sleep. The only change is appearance, based on class and/or religion.

I think 'John is meditating here.' would be more than sufficient. If we wanted to add more, we could just fix the fact that the action command only works if you're standing.