If you draft in the position where SJack is the pick (6-8) I think you should get him and westbrook if he is available in rd2. In rd 3 I would follow with one of the last few elite WR's available.
Option 2 would be Sjac then Holt/Smith/Owens/etc then follow up with Chester in Rd 3.
Both optios if all went well would leave you with 2 pretty solid RB's and an Elite WR.
This year I agree with what gnu314 said. 1-4 = RB, WR, WR. 5-10 = RB, RB, WR.
If I get a top 3 pick I'm going RB, WR, WR/RB (depending on the value left).