This is more about what I think the Mets should do vs. what I think they should do. I'm also going just with their current roster and not looking ahead to potential trades. I'll do that during the Winter Meetings.
I would give Juan Lagares every opportunity to win the CF position. I value defense. Especially up the middle defense. Bad defense adds to a pitchers, pitch count. Good defense subtracts from a pitchers, pitch count. It also minimizes the number of stressful innings for pitchers. I think most fans can see the immediate impact of extended innings due to poor defense but I think we greatly under estimate the roll over effect of poor defense. The toll it takes on a pitching staff during the course of a year.
Now to the infield.
3B is Reyes'. He needs to be in the lineup every day. I don't think Wright can handle that position anymore. He can no longer provide the defense that Reyes will and it takes to much out of him and his offense will suffer.
Pitching - I'm hoping and I think MLB will be going to a 26 man roster. I would like to see the Mets use that spot with a 6 man rotation if everyone is healthy. Syndergaard, deGrom, Harvey, Matz, Wheeler, and Gsellman. I would give Lugo a chance to win the 6th spot over Gsellman.