I go back and forth thinking it's the right time to deal Melo.
Appreciate his loyalty to NY.
Think he's still an all-star caliber/top 20-25 player.
However he makes 23 million, and that can get you 2 quality starters in this league. His scoring has not helped us become a great team, nor will it in the future. We need more players - more talent at multiple spots. Porzingis is still 2 years away from being experienced enough and in prime.
I go back and forth on this all the time, but I feel trading him now would be a good move for the longterm. If you can get Winslow/Dragic/(throw ins to make salaries work such as Anderson) I think that sort of deal makes so much sense for both sides, and you're not doing Melo wrong because he stayed with you as a free agent, you traded him to a place where he'll be with his buds (Bosh/Wade) and get to play on an EC powerhouse, in a situation where his scoring would actually be a real weapon (playoffs, crunch time, need elite 1 on 1 scoring).
All I think he does now he get you 5-7 more regular season wins, no playoffs likely, but also takes away from development of younger players and alot of capspace. The team scores just fine without Melo. It's not like him being on this team is making us great on defense (no way) or offense (somewhat important, yet still struggle with him to score).