The one problem I have with the new Efflorescence (besides the fact I can't spell it) is that it is an AOE triggered off an *oh crap* direct heal. I use swiftmend as a quick heal when someone drops really low. This is often not when I want an AOE heal. Maybe it will change my gameplay (and I'll use swiftmend on every cooldown), but it still feels like kind of a weird link between abilities.
I though it made more sense when it was triggered off regrowth, since regrowth seemed to be designed to be the basic raid direct healing spell. I understand that it was trigger too much, but I would have thought they could have changed it to something like...
When you case regrowth you have a 20% chance to trigger Efflorescence. Efflorescence cannot be re triggered for 20 seconds.
That would have given it a lower uptime (less than 33%) while still linking it to the more logical spell.