3) NY Mets replacement option for Buck Showalter: Eric Chavez
Had the Mets fired Buck Showalter during the season, Eric Chavez would've made sense as his replacement. Chavez was an incredibly accomplished player winning six Gold Gloves and a Silver Slugger for Oakland before settling in nicely as a Mets coach.
Chavez worked last season as the team's hitting coach before being promoted to bench coach in the offseason. He spent both years on Buck Showalter's staff playing a pivotal role, gaining knowledge and also getting closer with the players in the clubhouse.
Keeping things internal can make some sense as players are comfortable with Chavez, and at 45 years old he can adapt to the modern game better than a manager like Buck Showalter did. He'd be more open to changing things that might've worked 20 years ago when Showalter was not.
He hasn't managed just like Beltran, but has more coaching experience and connections with the entire clubhouse. He might be the easiest replacement to come up with and is one that would make a lot of sense.