The answer to this will be a lot clearer after the lottery.
If 2017 Nets is #1 pick then we go Fultz... anything else and I think its hazy. The only trade I would do that impacts our core would be Crowder and Nets 2018 for Porzingis (if he is available).
George has made his desire to play in LA too obvious and I wouldn't stake a 10-year potential all-star in a Fultz for 2 year rental. Butler simply isn't worth it. I believe Kevin Love becomes available this off-season as Cavs try to stock up on young, developing talent in preparation for post Lebron which is about 2-3 seasons away. I don't think he'll play past 35 with the number of business ventures he has going... and I think he wants to retire on top.
My opinion is that we don't necessarily need another "star"... we definitely need another scorer and we need athletic bigs that can rebound. Scorers such as Gay, Gallinari, Hayward works. Athletic bigs such as Griffin (if healthy), Skal, Porzingis also fills a gap.