Bane is a much better defender than Herro. I see them on a similar level offensively, but Bane's defense makes him much more valuable.
I think he's also much better on offense. Way more efficient, and just a much smarter player right now even though Herro may have a tad more shot creation. A lot of the metrics have the gap on offense as wide as the gap on defense. I don't know if I'd go that far myself, but I do think Herro has a ways to go to get on that level.