Those are good points.

I still think Zarate was the better bantamweight champion.

Look at Rodolfo Martinez' body of work before Zarate blasted him out. He ruined fighters whose subsequent lack of success was related to the beating Zarate gave them. For 3 years he reigned dominantly and violently until they robbed him against Pintor and he left the sport. I think you can say Olivares' opponents at the top of his list are a slightly deeper group, but Zarate usurps that a bit with his utter dominance.

Not to imply Olivares wasn't dominant. Or violent. But he reigned for only a year before getting stopped by Chucho. He won the return and a year later was stopped again by Herrera, ending his days at 118. That's a pretty unfair characterization of Olivares' reign, but I'm just pointing out that his dominance over his peers was not as pronounced as Zarate's. And no one will say the late-70's was a weak era at 118.

So what's more important, a few more good fighters on your "good wins" list or clearer dominance? It's a matter of personal tastes, but I can't get around the fact that Zarate was as dominant a force at 118 that I ever saw in my limited time on this planet. You certainly make a good case, but I'm gonna go with Zarate.