IMO Moira’s numbers are fine. Her heal stat’s the best in the game, her damage stat’s nothing to sneer at, and her survivability is great. Her problem is that she really doesn’t do anything special, leaving her with no real niche. Simply doing more heals without bringing anything else to the table doesn’t really do much.
I think probably the easiest thing to try is to simply adjust the passive qualities of Moira’s abilities. Lets say, for example, give her damage improved armor penetration, so she’s a particularly good pick if the enemy has a lot of armor. Or make her damage deal a little debuff, like -10% movement speed, or -20% heals as long as she sustains her damage.
I’d say her ‘bug fix’ should get un’fixed’, in any case. That was just unnecessary.