I would trade the pick for Cousins or George but no way I touch Melo. In my opinion Stevens will be able to seamlessly integrate Cousins or George into this team and they would push the Cs to the top 3 in the east.
However
As much as I would like to see this team pick up a star and make the quick jump to contention I can also see a longer build working very nicely. If the Nets for fill their end of the deal and get the Cs a top 5 pick I think this draft has real potential to yield a star player. Lets say the Cs hit a home run and get Simmons or Skal. From that I read Ingram may also have star potential. With that player (not to mention other first round picks) the Cs would have a sub 25 group next year of Smart, Rozier, Hunter, Mickey, Rozier, Sullinger (if resigned) and Young. In the 25 to 28 age range the Cs will have AB, Crowder, KO, IT and Zeller.
If things go as planned this season this very young team will make their 2nd consecutive playoff appearance. Adding a star in the 2016 draft will set the team up to take the next step to long-term success without taking a step back into the lottery. As a franchise I also think there is somthing to be said for the fact that Lebron James is now 30. A trade for Cousins or George would be this team on a path to potentially face the Cavs in the ECF. Not to say thats not challenge worth taking but the draft path could potentially create a team that can fill the void atop the east in two years when the Cavs will be faced with an aging king.