I would love Gay in a Raptors uniform, but I would rather have Millsap. I just don't see them being able to get both. Gay will eat a lot of that cap space up ($17M next season), and with their roster adding up to $59M in salaries next season, the Raptors would have to reduce a lot of salary to be able to get about $11/$12M under the cap to get Millsap.
$59M + $17M (Gay) = $76M
---> the cap is at $58M.. and say they raise it to $63M the Raptors would still have to shed $24/$25M so that they get about $11M under the cap and that does not include Jose's salary since it would already be off the books.
Even if they included DeMar in a trade, they still wouldn't have enough if they amnestied Andrea. They would have to create a wild 3 or 4 team trade that included both Andrea and DeMar, and then look to amnesty Kleiza.
I just don't see it happening.
Of course they could trade for Millsap and then use his Bird Rights to resign him. Something like
this.