Fultz is not a sure thing. He is also at a position Boston doesn't need (they are quite deep at guard). It makes total sense to trade Fultz straight up for Butler (who is a top 5 player in most advanced stats and locked into a ridiculously good contract for the next 3 years). The problem with taking Fultz and keeping him is that you can't really start him next to Thomas…that would be the worst defensive backcourt in the league. Further, Bradley, Smart, and Thomas are all free agents next year and all three will be getting 20+ million a year. I would hold on to the pick until free agency, make a run at Hayward (try to sign him) and then trade the pick for Butler. You then run out a lineup of Thomas, Butler, Hayward, Crowder, and Horford. With Rozier, Smart, Bradley, and Brown as your backups…Maybe try to swap one of those for a starting caliber PF/C. That lineup can contend with the Cavs.