Monk healers are much better than cata resto druids were. They're a bit squishy and lack mobility, but they have amazing output and use no mana at all. There's no reason not to play one in this bracket, especially at 24.
Enveloping Mist - Spell - World of Warcraft (the spell added to this level with 5.1) will tick for at least 700 per second. If you get that on someone they aren't dying. You just need to be very aware of your positioning, and having someone who can offheal next to you is a big help.
Tiger's Lust - Spell - World of Warcraft is amazing. You can get yourself away from rogues to heal up and keep moving or cast it on your FC/a dps trying to keep up with a druid EFC.
They aren't as strong as other classes, but OP heals are OP heals. Mistweavers are viable, its a fun class.