However, that said, it's not impossible. It would be an interesting theme to introduce to the novels, that of redemption, which isn't quite present yet, though there are hints of it.
I actually prefer Michael's son for the Sword of Love. Yeah, he's stupid, but I attribute that to the hotheadedness and thoughtlessness of youth rather than any inherent failing on his own part. Give him a few years and get him a life partner and a life of his own, and I think he really has it in him to be what his father was, or at least the ability to approach that.
The boy's nothing to be sneezed at even now. He stood up to an Elder Fetch unarmed and without any real hope, and to me, that speaks of a lot of courage and strength of character, even if it is untempered by experience and wisdom. Those can be learned.
Of course, I'm a cynic and I also see a lot of potential for that kid to take up one of the coins as well even if only in spite of not being "given" the sword.