I noted that the issues the team had early seemed to point to a coaching change - obviously that is still the case. However, managing is the one thing which is the biggest black box - where people flat out don't know what makes a manager good or bad. Teams have won with bad managers, teams have lost with good ones - it's not simply as reductive as wins.
Farrell coming back is fine - there is a decent chance Lovullo will be gone ... he's clearly one of the most qualified managerial candidates out there (even before his acting stint with Boston), and could be on any number of shortlists. I'd also think Lovullo would not want the job in Boston anyway based on how the circumstance would have to play out. Tactically, Farrell is solid - he certainly has never had a greatest hits of howlers like Matt Williams did this past season, nor even what Ned Yost has done (and of course Kansas City is winning despite it). The guys clearly respect him.
In a lot of ways the biggest mistakes the org made were setting the club up in 2014 for the title defense - too much wishing on stars (in the outfield) that had a lot of risk associated with it. (that Victorino could stay healthy or that a Nava/Carp platoon could still work, JBJ). 2015 clearly did not go well, but a lot of it was hasty makeup work for 2014's non-moves.
Pitching's gotta be better - duh. How that manifests itself between rotation and bullpen, I honestly don't care. Just make it happen. The lineup is largely set - and looks to be quite good. Of course, if the Sox wanted to take their coffers out for a walk and look at a Jason Heyward (or a Justin Upton who fits the classic LF mold more cleanly), I would not have any real issue there.