Well, a villain with a backstory that mirrors ... Batman, Dick Grayson, and crosses over into their Venn diagram in the past with connective "shared backstory" isn't out of the ordinary. Heartless feels requisitely Snyderian in that regard. But I think the execution is satisfactory, and I think he's thematically appropriate for Dick's "Act II" villain of the run. Nightwing didn't yet have a "body harvester villain" yet, either, so kudos. It's the cheese version of grimdark but it's kind of funny in that aspect.
I've been reading less analytically for a while now, so I did kind of smack myself for not realizing "hey the bully from that flashback is probably the guy".