Here's something that addresses needs for both teams if Bosh leaves or not.
We get to experiment with a 7'3 big who hasn't really gotten a chance to show his true colours as an early injury in the season sidelined him. If Bosh leaves, Thabeet can slide to the starting centre while Bargs moves to the 4. This doesn't even include a consistent
scorer in O.J. which he is pretty much like his USC counterpart DeMar(except where Raptor fans hope DeMar will be in 2 years). If Bosh stays, we have a second overall pick(from what looks like a pretty good draft year) that can be potentially be traded for a variety of scenarios in the future and still has a lot of upside.
Zero sum gain when it comes to defense, although you might say that Toronto wins by having the less bad defensive players in this trade.
Do we really need more offense?
What if DeRozan actually turns out to be T-Mac 1.2?
Can Marcus Banks be a serviceable pg?
Turkoglu starts complaining that he's handling the ball 3.2 more possessions than he did in Orlando.
Marc Gasol seems to be playing well with Randolph and Memphis is one of the best rebounding teams with their current frontcourt, leaving Thabeet on the outside looking in. Calderon boosts their playoff chances this year and gives them a true pass-first pg where he won't disrupt the offensive output of Gay and Randolph while shooting a high percentage whenever he is called upon. Not only that, but they get a serviceable backup in Rasho and someone who has a lot of similarities to Mayo - and as a biased Raps fan - DeRozan has a good chance to be there in a few years given the right opportunity. After all, if they can develop Mayo, why not DeRozan?
Trading risk in a player like DeMar, why do it all over again?
Calderon is injury prone, can he handle minutes? Defense...
Memphis has a strong young nucleus - and with the right additions - might take them to the playoffs in the west for many years to come, why would they break it all up?
We are pretty much covering our bases if or if not Bosh leaves.
We get rid of the most probable odd-man out in the ball handling carousel and gives us a solid scoring wing.
We eviscerate the horrid Calderon/Jack/Turkoglu lineup.
BC era will have come full circle as Calderon was the last player originally not part of his plan.