I agree with all of the above. I have also decided the it's best to use Selene most of the time anyway (while clearing trash, the DPS boost is better, I think), so I only need to manage Eos' group heals manually on boss fights. And most boss fights get frantic enough that I want her group heal the moment it becomes available by the middle/end of the fight, so there's not a lot of management to do once things get serious. Selene's buffs are pretty easy to juggle thanks to their long recast timers.