What they ought to do is trade Hernandez. They won't, but they should. Bring up Tatum to back up Hanigan.
It's a risk, I know, but it would save a lot of money.
Hanigan has earned the starting catcher's job, it's undeniable. But they won't do it. They'll start Hernandez behind the plate and Hanigan will play twice a week.
Hanigan should be batting second in the lineup, even first until the team gets a genuine lead off threat. If Willy must play, hit him at the bottom of the order unless and until he gets going.