I would keep what you have. I like Sproles for the simple fact that he's a PPR stud. Saints have to get it together at some point. Last year he was a first round value in PPR. I like Maclin as a more stable threat at WR over Nelson.
QB- Roethlisberger, Rivers, Foles
RB- McCoy, Lynch, L James, Ivory, F Jackson, D Thomas, Turbin
WR- Julio, Bowe, D Bryant, D Jax, Amendola, Broyles, Gordon, Hill
TE- Celek, D Allen
D- D Washington, S Weatherspoon, L Kuechly