I can think of worse players to bring into Boston, but I would want to get a hard 'NO' from the agents of Hayward, Griffin, and (of course) KD before moving forward.
In a world where we do bring in Vuc, we would also likely lock up KO and JJ since they would no longer be cap casualties. We should also trade Amir and not Zeller since Z's non-guaranteed contract can be used for an additional trade at the beginning of the offseason (i.e., Zeller, AB, and BKN pick for Butler (I know, too much).
A world where we have IT, Butler, Crowder, Vuc, And Horfird with Smart, Brown, KO, and JJ off the bench is a pretty good world - especially with the '18 BKN pick still in hand. And let's not forget about Zizic and Yab, too.