Agreed. The big issue with Carmelo at this point is he's a 2-3 option who thinks he is still an alpha. He can still score, still create, and give you useful minutes. So, if you change his environment, get good coaching and a legit organization around him, perhaps give him a sniff of actually winning maybe he buys in. And if not, you've preserved your space for next year (agree on the player option, though may need to pay some for him to decline).Carmelo doesn't sound like the craziest idea to me if Hayward chooses to play elsewhere. The dropoff from Hayward to the next best free agent is enormous(not counting Durant). I'd rather just take Melo into my cap space for a year rather than sign a Rudy Gay or Danilo Gallinari for multiple years. Don't love the Melo fit either, but NY would probably just give him to you. I'd want him to decline his player option for 2018-19 to take him tho.
Definitely not my first choice, and I'm not super optimistic it works, but I get why you might try as a fallback