Well, I understand that Schwarber may not like 1B, but he probably needs to accept that it is his future. He is horrible in the OF and while the number of chances increases by going to 1B, I believe it is still considered the easiest (least athleticism needed) defensive position.
Very few guys can play the OF but can't play 1B (really height is the only issue that can cause that to happen). Schwarber may need time to adjust, but it is his future I suspect.
Problem is we can say the exact same thing about Castellanos. Maybe even more so.
Bohm probably doesn't have the bat to really even be more than a backup 1B / alternate.