The following rankings are not specifically for dynasty drafts but in the 'RBs are worthless' thread I shared early fantasy rankings by a Chicago paper within the last week so this is current. Here are the top 20 players listed in order.
Arizona RB David Johnson is ranked 11th.
1. Antonio Brown, Steelers (1)
2. Julio Jones, Falcons (2)
3. Adrian Peterson, Vikings (3)
4. Todd Gurley, Rams (4)
5. Odell Beckham Jr., Giants (5)
6. DeAndre Hopkins, Texans (6)
7. Le’Veon Bell, Steelers (7)
8. Marshawn Lynch, Seahawks (8)
9. Rob Gronkowski, Patriots (9)
10. David Johnson, Cardinals (10)
11. Cam Newton, Panthers (11)
12. Tom Brady, Patriots (12)
13. Dez Bryant, Cowboys (13)
14. Allen Robinson, Jaguars (14)
15. Aaron Rodgers, Packers (15)
16. Carson Palmer, Cardinals (16)
17. Andrew Luck, Colts (17)
18. Doug Martin, Buccaneers* (18)
19. Devonta Freeman, Falcons (19)
20. Russell Wilson, Seahawks (20)
I argued that thread that there are more WRs on a typical play so there are more productive WRs over starting RBs so obviously there are more WRs to choose from so it is easier to find top WRs in the 3rd/4th rounds. Knowing the cold hard numbers to choose from I would not rule out taking a RB in the first round.
If players go off the board in the order ranked and if you hold the 11th pick in the 1st round and the 14th pick in the 2nd round then you could come away with the 5th ranked RB and WR. If owners go WR/WR in the 1st and 2nd rounds and they held those same picks they would wind up taking Dez and A-Rob and then they'd have to find a RB in the 3rd to match DJ at RB.
So heading into the 3rd round, one owner would need a number one RB and the other would need a number two WR.
Here are the top-five remaining top players listed:
- Brandon Marshall, Jets
- Mark Ingram, Saints
- LeSean McCoy, Bills
- Jamaal Charles, Chiefs
- Demaryius Thomas, Broncos
You would have to figure that of the remaining players that the top-five players have the highest chance to go off the board which would leave these five players.
- A.J. Green, Bengals
- Jordy Nelson, Packers
- Ben Roethlisberger, Steelers
- Drew Brees, Saints
- Blake Bortles, Jaguars
Two top ranked WRs but no top ranked RBs.
I'd rather go into a season with team comprised of RB David Johnson, WR Allen Robinson, and WR A.J. Green then a team with WR Dez Bryant, WR Allen Robinson, and a 30+ year old RB Frank Gore or a Chris Ivory or whoever is left to pick from in the 3rd round as my top RB.
Back to where DJ is ranked or when he should go off the board. It depends on when your first and second round picks come up and who was taken and who is available but using this example I wouldn't rule David Johnson un-draftable in the first round especially if it were a dynasty start-up. I'd much rather have him over some older RBs who I would likely be choosing from in later rounds as my #1 RB.