This seems to be the crux of the naysayers arguments, so of course we should ask the question: what do you expect from a first round running back? We'll go ahead and ignore draft position for now, but we should acknowledge that it makes a huge difference. A top 10 back is expected to perform better than a back drafted in the lower third of the round.
From the 1999 to the 2009 draft, 34 running backs have been drafted in the first round. How does Maroney compare? It depends on how you slice it. His YPC is better than Deuce McAlister, Jamal Lewis, Joseph Addai, Ricky Williams, Thomas Jones, Edgerrin James, Darren McFadden, Kevin Jones, Willis McGahee, Marshawn Lynch, and 9 other players. That puts him at 15/34. So from a YPC perspective he's average for a first rounder.
His totals are on the low side, e.g., total carries and total yards. But this can be explained by how he is used. E.g., he is part of a rotation and the Pats pass more than they run lately. So rather than totals we should emphasize things like rates and averages as they tell us what happens when he does get the ball.
So what is his TD rate? He scores on 3.12% of his carries, good for 17/34. Not great, but average for a first round back. His receiving TDs rate is 3.13%, good for 25/34. That's definitely on the low side, but also not a primary expectation of a running back (not to mention that it's certainly not one of the complaints given by members of this board).
How about his yards per reception? Maroney averages 10.81 yards per catch, good for 2/34. That's a stellar number. He's definitely overperforming in that area.
How about total fumbles and fumble rate? Maroney's only fumbled once and lost that fumble. His fumble rate is .22% (that's correct, there's no decimal error there), good for 1/34. A stellar number, and something this team certainly values. Less important is his fumbles lost rate, which is also .22%, which ties him for 2/34. The guys than him or tied with him for fumbles lost rate are rookies.
So what makes a good first rounder? Being at least average compared to other first rounders should be a fair criteria, and in all meaningful categories except maybe one it seems like Maroney is either average or better than average and sometimes stellar when measured against other first round running backs drafted in the last 10 years. When he gets the ball, he's pretty good.
Here are the numbers/ranks:
Total Carries Rank
449 = 24/34
Total Yards Rank
1938 = 23/34
YPC Rank
4.32 = 15/34
Total Rushing TDs Rank
14 = 22/34
Rushing TD Rate Rank
3.12% = 17/34
Number Receptions Rank
32 = 27/34
Total Reception Yards Rank
346 = 23/34
Yards Per Reception Rank
10.81 = 2/34
Total Receiving TDs Rank
1 = 22/34
Receiving Touchdowns Rate Rank
3.13% = 25/34
Total Fumbles Rank
1 = 1T/34
Fumble Rate Rank
.22% = 1/34
Total Fumbles Lost Rank
1 = 2T/34
Fumbles Lost Rate
.22% = 2/34
I'll try and upload the spreadsheet I used to assemble the data and post a link. If anybody spots any errors (I kind of breezed through this this morning) please let me know. All the stats are from NFL.com or extrapolated from those stats.