Better than most proposals on the blog. I agree this on the light side of value for the Cs, but overall I think it makes some sense. And given the choice between this and nothing before the deadline -- I'd do this, though I think you could remove Bass and Nelson from the equation.
Two issues I see here: 1) Do Memphis and Cleveland want to make each other better?, and 2) Memphis gets thin at center. Assuming you get past issue 1, I think you could simplify this deal to be:
To Memphis: Green, Wright
To Cleveland: Kostos
To Boston: Prince, Adams, MEM 1st from CLE, Hayword, a little filler from one or the other.
Or,to make this deal more sensible for both other teams, you could do it sooner as two separate deals:
Deal 1 ~
To Memphis: Wright
To Cleveland: Kostos, Cathetes
To Boston: Haywood, Stokes, MEM 1st from CLE
Deal 2 ~
To Memphis: Green
To Boston: Prince, Adams
But, all in all, I give you a TP for the overall idea