We can add to our shooting guard collection in this deal.

Seriously though I wouldn't pull a trigger on a deal like this until we are well into the season, and see what Mclemore can do in real regular season games, and how bad or good the Kings are. If Cousins is carrying them to maybe the 5 to 10 draft range then it gets a little more dicey. I might demand 2 future number picks, and Mclemore for Green and Rondo, and filler on both sides to make the numbers work.
The plus side for waiting until midseason for a deal like this is also less of a chance a Rondo, Green, Cousins mix would push the Kings close to playoff contention.
It is still a very risky deal no matter how you look at especially if Mclemore flops, and the draft pick if closer to the 10 range will be riskier.
If we go this route we might as well trade our other veteran role players Humprhies, Bass, Lee, ect for whatever future value we can get for them. Not crazy about it though.