I am certainly not opposed to trading Rondo, but there is no way I would even consider that trade. Now if it is Rondo for McLemore, Stauskas, Williams, and a couple of firsts (say 2016 and 2018). I would seriously consider that.
How about this 3 team
Boston - Stauskas, McLemore, Williams, Singler, Dinwiddie, Sac 2016 1st, Sac 2018 1st, Det 2015 2nd, Det 2016 2nd
Sacramento - Rondo, Smith, Jerekbo
Detroit - Green, Thompson, Terry, Outlaw
I think that is a reasonable trade for all parties (if Boston is going full on rebuild). Boston goes all in on the rebuild, picking up some more young players and draft picks. Sacramento gets Rondo and Smith to pair with Cousins and Gay. Detroit picks up Green to replace Smith saving a bunch of money in the process and getting a better roster construction and fit (Green is a much better fit with Drummond and Monroe than Smith is).