I'll take Casas as an over based on his OBP.
On the mound, Bello will be an under when he realizes he's better off with swings and misses rather than pitch to contact with the Sox' D behind him. For the same reason, the ERAs of Sale and Kluber will be worse, because they just can't put away hitters like they used to.
The swings of Turner and Duvall may benefit playing in Fenway, though Turner has at least shown he knows how to go with the pitch. Based on career OPS, one of them should be over your projections, and one of them under.
JT's career: .832.
Duvall's career: .755.
At this point in their careers, I just don't think either will play a full season injury-free.