This is written for a general audience in mind, who do not necessarily play mistweavers.
Gift of the Naaru (GoN), a draenei racial. 3 minute CD
It heals the target of 20% of the caster's total health over 5 second, or a baseline of 4% a second. Its an instant spell.
On the surface, the buff to this racial turned it into a bursty HoT, but may still seem unimportant as a spell as a healer. Why is this significant in WoD? Well because with the doubling of health pools, and the triage model, it means that this racial now heals 4 times as fast, for twice as much relative to before, with much less overhealing. Already this makes a perfect "oh shit" button, that you can cast on a dying tank or a person taking a crap ton of damage from a dot in the prepatch, and in WoD with all the changes finally being seen in the first tier, this spell will have guaranteed uses.
Now specifically for mistweaver monks, this spell has several interactions with their abilities that many people do not know about.
As a spec, we will be focusing on multistrike and crit, both of which affect the 4% a second HoT from GoN, which is significant for crane stance later on especially. This means that our stat priority min/maxes the effectiveness of this spell in particular, which no other healer does.
As a Mistweaver, we have a spell called Life Coccoon. We all know it as the big green bubble that prevents a lot of damage with a big absorbing shield. This spell has a secondary effect that was not really utilized in MoP, in that it increases all periodic healing by 50%. This secondary effect was somewhat useless in MoP, because of the nature of bursty damage and healing, periodic bursts of healing caused mostly overhealing. This will change in WoD.
Life Cocoon interacts with GoN to produce a 30% burst heal over several seconds, or 6% a second. Now in WoD, Life Cocoon will have a 1:40 CD. Because GoN has no GCD, we can macro in GoN with Life Cocoon to produce a very bursty hot on top of our shield. In cases where you would react to put Life Cocoon on someone, they are usually of low health. This leads to very little overhealing from GoN that is 50% more potent. With a single button you can prevent a person's full hp bar in healing + absorbs with every other Life Cocoon cast. Keep in mind, because GoN also is empowered through crits and multistrikes, as a healer in mythic SOO, with 40% crit, or 60% in crane stance, and about 12% multistike with trinkets and buffs, you can expect about a ~50% heal, or 10% per second. Not so useless now.
On top of that, in Crane stance now, we get a 20% increase to our critical strike for 20 seconds when we use Blackout kick. If we are fistweaving in a portion of a raid when someone takes massive damage, you can cast Life Cocoon + GoN on top of a 20% critical buff which will affect the racial further.
On my mythic Thok fight a few nights ago, I did 21.5k HPS. I casted GoN twice, which took a person from 20% HP to 75% in 5 seconds, and had nearly 0 overhealing. As a comparison, this led to a near 1.8% amount of my healing for that fight, or about 100k, which is higher healing benefit every single other racial in the game has for mistweavers. But its main benefit is in its utility, not its HPS throughput.
On the plus side, as a draenei, you get what seems to amount to a little over 1% more int for free in current SOO gear, which already makes us one of the best healers. This racial scales throughout the expansion, and because it awards a primary stat, is always helpful to everyone.
TLR - All the elements of mistweavers, plus all of the healing changes actually maximize the potential of this racial to such an extreme that is better than a great deal of other single target class spells for healing in WoD. It amounts to healing that was most likely not initially seen when the racial was first designed, and so from my point of view, Draenei will be one of the best races as a mistweaver in WoD.