Since some of the best running backs in the game ( Le’Veon Bell, David Johnson, Ezekial Elliot, etc) can score as many points as the best quarterbacks in fantasy football, it is in your best interest to take one your very first pick in the draft if available to you. Between your first four picks, you will want to have grabbed at the least 2 running backs to max out your starting roster because after that it is very difficult to find any starting quality backs. It is important that you be focused on drafting the best player available to you in these first four rounds. After you pick up these two, you’ll want to pick up at least two more running backs if not three to be in your flex or on your bench as backups. You’ll want to pick these RBs up after you have filled all of your other starting positions including 1 QB, 2 RB, 2 WR, 1 TE, 1 Flex, (not including kickers or Defenses). This is where you could go after ‘sleeper picks’ (players who have the potential to do really well, but no one knows how well they will actually do).
As for wide recievers, I personally think they have a similar importance to running backs in Fantasy Football and see that it is smart to have at least 4 total on your team and to take 2 of them between the 1st and 4th round of the draft. Like running backs, there are only a few of them that are consistently high scoring players. I would however say that they're are more of them than there are consistently high scoring running backs. The last 2 wide recievers you pick up should be ‘sleeper picks’ and should be picked anywhere after you are able to complete your starting positions which include 1 QB, 2 RB, 2 WR, 1 TE, 1 Flex, (not including kickers or Defenses).
*The Flex position is where you can put any position players of your choosing (RB, WR, TE) not including a QB, Defense, or kicker.
Round 1-WR or RB
Round 2:RB or WR
Round 3-WR or RB
Round 4- RB or WR
Round 5- TE or QB
Round 6-QB or TE
Round 7- RB or WR
Round 8-WR or RB
Round 9-RB or WR