Looking at the individual players on this team...
Hanley Ramirez has a .795OPS, just a tick below his OPS from last yr. He's hit 1 less HR than he did all of last season. He's probably gonna hit a bunch more. He'll likely end up in the 25HR range this yr and should have an OPS over the .800 mark. Fangraphs has him as a slight minus when combining offense and baserunning for his position. But his defense has been abhorrent. He has a UZR/150 of -44. That's not a typo. He's a good offensive player, he's right around where fangraphs expects him to be offensively for his position, but he's a dumpster fire on a sinking ship defensively. He likely has a short rope in LF before you find a new spot for him, where I don't know
Pedroia has been chugging along mostly off the radar right at his career norms offensively. Almost exactly at his career average in terms of BA, OBP and SLG. On defense, he's grading out about average this yr (UZR/150 of -0.4) which is not really like Dustin. Either way, his demise was predicted far too soon.
I like Brock Holt. The kid makes good ABs and actually plays good D all around the diamond. He's been an excellent utility guy to this point, but because he started hot, he is starting to get over exposed. He is an option defensive in LF as Hanley sucks ass out there
I don't know what you can do with Napoli. The luck numbers point heavily in him turning it around. But just as soon as he gets hot, he cools off. If he starts to go into a downturn again, you might consider Hanley at 1b or Hanley at 3b with Panda moving to 1b and moving Holt to LF. Napoli isn't horrendous defensively, but he's not magnificent either. Also, Nap is smoking lefties this yr. .920OPS and a .364OBP.
David Ortiz has been a mystery to some as well. But looking deeper at the numbers, you see a bit of a trend here. Ortiz is absolutely getting abused vs lefties this yr. .121/.119/.172 is his slash line in 58ABs. That is not a typo. No walks, no HBP's, no HR and just 3RBI. Look at the slash vs righties. .278/.392/.500 for a .892OPS. That's more Ortiz like right there. If things continue, having Nap and Papi platoon might give you your best lineup.
The rest of the guys you have to deal with. Panda has ditched batting righty and has to stay in your lineup. Bogaerts is your only SS option and you kinda need to see if he puts it together. For now you have to live with Mookie and Rusney out there. And at C, you have to live with Swihart and Leon because of injury.
But if you moved Hanley off LF and put him at 1b or 3b (which would move Panda to 1b) and pushed Napoli to a DH platoon with Papi and moved Holt to LF (temporarily until you find a better LFer, which isn't too difficult on the market) you improve D while removing some liability offensively