They boosted their rotation, which the Red Sox trash them all season. Their bullpen to me depends on how Britton holds up. How Ottavino adjust to the AL East. Which Batences shows up. We whack Chappy all the time. Their offense needs no introduction. They have made moves to improve their weaknesses.
The Red Sox better get A LOT more out of 1B, 2B, 3B, CF, C next season. If they aren't better next year we probably will not repeat as division champs.
in terms of WAR we rank last season:
1B 18th
2B 22th
3B 27th
CF 15th
C 30th
Those are quite ugly