An increase in Bello's fastball spin rate would probably take him into #2 territory as soon as next year. It's the only thing holding him back from plus strikeout numbers.
I've been pleasantly surprised with Pivetta's work out of the bullpen. One of the reasons I was down on the guy was his arrogant demeanor when asked by reporters if he was willing to go to the BP, but it seems like he's all in on the move now. The benefits of having a manager respected by his players like Cora.
Overall, Montgomery had a 3.94 ERA and 108 ERA+ with the Yankees, and a 3.44 ERA and 120 ERA+ with STL. Let's not pick nits, he's been better with the Cards, but not by an earth-shattering margin.
I don't get why people are so surprised abour Duran succeeding. He has all the tools. Buyer beware on the BABIP, but he has top flight speed, which partly explains it