Update as promised.
Ran this on Mythic BOD. Felt like it was burning mana relatively fast on Champion. Mid-way through, I had to stop and manually cast because it was only casting Smite. Tried it on trash after, kept casting smite and missing shield for whatever reason. Didn’t try it again after that. wasn’t sure what the problem was and didn’t have time to look.
However, while it was functional, it was doing amazing heals.