I just spend some time reading about Yordano Ventura, and I got kind of excited about him. The Royals could actually have some real, quality pitching depth after the ASB, if Duffy and Paulino come back and Ventura is ready. I expect that Ventura will in fact be ready; they should promote him and Zimmer sometime soon, at which point Ventura will be waiting in Omaha. Yost's comments during spring training suggest that he also thinks Ventura is close.
Now, in his first two starts of the season, Ventura has gone five innings and struck out a lot of guys. Which made me think: why not stack him with Duffy or Paulino? Presumably Duffy and Paulino may not be totally stretched out, so stacking might make some sense. A Ventura/Paulino #5 starter would potentially be one of the nastiest in the league, and would be a real strength; in fact, such a pairing might function as the second front-of-the-rotation starter that the Royals need. The third guy of the Ventura/Paulino/Duffy trio could be a fireman-type reliever or a spot starter.
Of course, the idea of stacking starters is not mainstream, so the old-school Royals might not go for it. It does look like an exciting option though, and I hope the Royals strongly consider it.