Not sure if individual players return yardage counts. If it does you should definitely keep sproles (which you should anyway). I also agree you should keep freeman. In a 16 team league you'll be hardpressed to find someone better in the draft. And keep Maclin, remember he had that illness coming into the season last year and should be much healthier and hungrier coming into the season this year.
Maclin
Sproles
Freeman for me
12 team dynasty league
H2H:G,A,+/-,PIM,PPP,SHP,GWG,Hits, W,GAA,SV%,SO
Daily Lineups: 2C,2LW,2RW,4D,2G,2UTIL,5BN
C: Datsyuk, Kopitar, Sedin, Staal, Ott
LW: Ovechkin, T. Ruutu
RW: Hossa, Horton, Backes
D: Lidstrom, Edler, Enstrom, J. Carlson, Boyle, Shattenkirk
G: Luongo, Miller, Rinne
5 prospects(40game limit): B. Smith, Lindback, Toffoli, Calvert, Morin