If I had to choose one of the big 3 (Bogaerts/Bradley/Cecchini) to part with, I think I'd choose to part with Bradley. That said the most we should also throw in is one of those RDLR/Owens/Barnes/Ranaudo/Webster arms, and that's only if Philly is eating a lot of money, which as SFF notes, can help us retain Ellsbury to make up for having just traded JBJ. Otherwise it should be JBJ and a few of the 10-20 level prospects. I'd say Workman but he's kind of busy right now.
And if we're trading JBJ for a starter not named Lee then it's automatically a bad trade imo.