[Kuritza]

For the communion thing, making slaves passive will render many nice mages like Astrapelagists or LA Marignon's seafaring mages (whatever) semi-useless, and others like Celestial masters quite average. Also, the nice synergy betweeen communion and sabbath is gonna suffer.
So if this communion thingie is gonna be fixed, make it so that 'slaves dont cast if at least one master has cast anything the same turn', not 'slaves dont cast spells at all'. Thus communions will become more balanced, but still usable. Otherwise they will exist perhaps for casting heavy BF enchantments only.

Regarding VotD - this spell goes against the logic and normal game mechanics. This exception should be fixed if only because there's no protection against it (as against the Mind hunt) and its selective. MR *will* fail you sooner or later, most likely sooner.

Immortal demons - gosh, its not OK and it wont ever be. These who advocate it are either clueless or abusers themselves. Dakini, for example, are damn dangerous even naked; make them immortal and Lanka becomes undefeatable period.