Well, with the buff to the duration you can actually throw out many healing rains and keep those up if i have understood it correctly, but yeah, the healing has never been that great in a raid so i don't think i will be rolling with conductivity in a raid next patch
It isn't a overwhelming change to soloing,but you benefit greatly as elemental to not having to cast healing rain more than once(depends on encounter).This allows you to get more dmg and healing output and don't have downtime all the time.