Without commenting on the proposed ability itself, Blizzard will not give priest a fun, thematic, and interactive spell. Blizzard said they really like how interactive priests are in PW:GFY but, in practice, priest is one of the least interactive classes in the whole game. Just take a look:
Angelic Feather: Theoretically extremely interactive, but priest mobility is so terrible that it is almost exclusively used for personal mobility. Blizzard knows this but, instead of addressing the problem, they shoved the solution into the oracle tree.
Body and Soul: Only interacts with allies as discipline, and even then it’s rarely taken due to its placement in the terrible class tree and is never used to provide movement speed to allies because every other class has a superior option if mobility is needed.
Leap of Faith: Theoretically very interactive, but priest’s terrible mobility means that it is usually used only on other priest or on a player that made a huge mistake, and so is used maybe once per encounter/raid/dungeon if we’re being extremely generous or, if we’re being real, not at all for most players. Also strictly worse than its child, Rescue, which has a much shorter cooldown and gives incentive for regular use even if the movement isn’t needed.
Power Infusion: Not fun and not interactive, though I recognize that’s just an opinion. Give it some audio/visual feedback to make it feel cool to buff your friend and then we can start talking.
Time Spiral/Blessing of the Bronze: Uniquely provides no value to priests.
Wind Rush Totem: Priest is not alone in receiving zero value from Wind Rush Totem, but it is one of a minority of classes that receive no value from it.
Stampeding Roar: Same as Wind Rush Totem, but priest does receive minor benefit from Stampeding Roar.
Not only does priest itself have an extremely slim list of abilities that are interactive with allies, they’re not strong enough to be used regularly or must be used exclusively by the priest to shore up its anemic kit. What’s more is that priest receives less interaction from other classes than every other class in the game due to its mobility being supplemented by group cooldowns less than every other class in the game.