Trade makes far more sense with Boston just absorbing Capela into cap space and Philly getting Gordon and Tucker from the Rockets. Some other minor pieces can be in the trade, but I think that is how it would shake out. That is if Philly knows it is losing Butler anyway. I actually think Gordon and Tucker are great fits there (I don't mind Capela going there either from their perspective, but I could see them rather having him go elsewhere and picking up a 2nd round pick or two in the process).
So something like this
Houston - Butler, Bos 2nd
Philly - Gordon, Tucker, Yabu
Boston - Capela
Boston then pursues a veteran PG with the remaining 10 million or so in cap space - like say Rubio.
So post-trade
Guards - Rubio, Smart, Langford, Edwards
Wings - Hayward, Tatum, Brown, Semi
Bigs - Capela, Williams, Williams, Theis
Pretty decent mix. Probably not a championship contender, but should be a clear playoff team with room to grow into a real contender if Tatum and Brown continue to improve and Hayward can get back to his Utah days.