It would certainly help get the danged healing out of essence. . . those monk lists are mentalism lists, really. . . .
Monk magic: Generally Self Directed
Bard magic: Generally Other directed
Which sounds like essence, and which like mentalism?
Other than that, I'd suggest:
Raise bard armor costs, since they will be unable to wear armor as essence users anyway.
Drop Monk armor costs. . .they can choose to be an Adrenal Defense monk, or an armored monk now in mentalism.
Drop the attunement and runes costs for Bard
Raise them for Monk.
Technically, you should also raise the bard's weapon costs, and lower the monks, since the bard will be hard pressed to even carry weapons due to essence realm limitations. . .(Frankly, a mentalism semi is perfect for an armored-armed warrior. . .which you get in the companions) But you can ignore that, and just advise the bard to orient toward bows or clubs to avoid metal.