I don't think healers need more complex dps rotations, but rather new skills and traits expanding on their secondary identities.

In WHM's case it would translate to more skills that do damage and heal at the same time. oGCD's to heal or damage to weave with healing or damaging spells.
WHM's identity of the nuker would benefit from a playstyle that weaves damage and healing together. No utility translates to huge personal dps.

AST doesn't need more dps tools, but rather new ways to expand on her buffs. Maybe a revamp of royal road, time dilation and new card mechanics so that the player truly feels an impact everytime he draws a card.

SCH would be the debuffer/enfeebler of the three. Have its ocd's no longer consume AF but rather fey gauge. Then use AF to apply debuffs that either reduce damage done or increase damage taken to a single target. Like a Scan ability that'd reveal weakpoints.