Yep, learn to use Selene on Obey. If you have her on sic, and she blows Fey Wind right when all the mobs die it makes you look really cool doesn't it? On-Sic Fey Caress likely gets used up by a Warrior's pacification. If you have a Bard in the party that is on-top of Warden's Paeon already, you just wasted the cool down. Back for Mind Blast in Midas Savage, Silence was a decent emergency use if you were on-top of it.

The downfalls of using Selene on-sic have changed quite a bit this expansion.

As for Eos, it's not so much of the question of Whispering Dawn being useful, it's the fact you can have a free roused regens every minute. Anytime you can prevent the other healer from having to GCD a party-wide regen, or you are helping them from casting multiple times you are doing a service to them and yourself.