Here come my very humble opinions. This list is based on not only talent, but production and playing-time (i.e. being able to stay healthy and in a game). If you don't like what you see, don't fret, because at least half of these guys will prove me horribly wrong come week 8. This is a no-rookie list.
01. Ladanian Tomlinson
THE undisputed all-around runningback in this league. He's got the size, the speed, the feet, the hands, the toughness - everything a runningback needs in order to be successful.
02. Edgerrin James
If he didn't lose quickness after two knee surgeries, I think he'd rival Tomlinson as the guy that has all the tools... but we knew that watching him in college, didn't we?
03. Shaun Alexander
A pure runner. He goes down a little too easily for my tastes sometimes, but the man puts up staggering numbers that can't be easily attributed to offensive line play, in my opinion. That case could be made moreso for a few of the upcoming backs. At his age, he's still got several years to run strong.
04. Deuce McAllister
Endless talent on this guy. Nagging injuries have hampered him in the past, which makes me only wonder what he could do behind a better line, and healthy throughout a season. I prefer runningbacks with some pounds on them, and while he's got some to spare, it doesn't seem to slow him down any.
05. Jamal Lewis
More nagging injuries/off-the-field problems. However, his combination of size and speed give him an advantage over other backs. You can't overlook his amazing 2003 season. It's a testament to his ability.
06. Priest Holmes
I said that offensive line dominance would penalize some other feature backs. This is just my opinion of course. Still, Priest is one of the more aware football players, I've ever seen run the ball. He'll find the hole every time.
07. Curtis Martin
When will this guy retire? By the time that happens, you'll hear a collective sigh of relief out of the entire AFC East. For a guy with sub-par speed and size, he's pretty good. Curtis is another one of the most aware players I have ever witnessed. The man has eyes in the back of his head.
08. Ahman Green
Green puts up huge fantasy numbers, despite his fumbling. I'd attribute some of that to the often overlooked Green Bay offensive line. But you wouldn't be a top NFL runningback in my mind if it was all the offensive line. Green can cut through the hole as fast and as hard as the rest of them. We could see a decline in his statistics this year as two Pro Bowl guards just left the team, but I have a feeling Green will do just fine.
09. Corey Dillon
Tough runner with explosive speed that is awfully similar to a player we have. With a more consistent offense, we saw Corey finish 3rd in the league in yards last year. He's not done, and I hope we've shored up a better run defense for when he comes to town.
10. Clinton Portis
Slender Clinton relies on supersonic speed. This guy couldn't play "Wad ball" if he wanted to. However, that doesn't mean I don't recognize the most explosive running back in the league. Behind Denver's infamous offensive line, he put up almost unprecedented numbers for such a young 'back, and had he been traded to a team not named the "Deadskins," and to a team such as Kansas City, we might see Priest Holmes splitting serious time.
11. Tiki Barber
So underrated, it's really ridiculous. Tiki does so much for the Giants that you have to give it up to him. He's good for one really big play a game, and his team doesn't really help him get there.
12. Willis McGahee
Obviously talented. I don't know why Dolphin fans dispute it from time to time. With that said, he's still got some proving to do. That 4.0 ypc can go in either direction this season, his fault or not. But when making this list, I knew I'd rather have Willis on my team than Julius Jones.
13. Julius Jones
Like Tiki Barber, he knows how to make the big play. If you haven't caught the highlight reel of All-Time Cowboys running backs that is circling the Internet, I suggest you check it out. His game isn't complete, because I don't think he could carry an offense like many of the guys above, but boy does he have serious moves. In a clicking offense, he'll be unstoppable, shadowing Emmitt Smith, perhaps. It's really to bad that the 'Boys had to resort to Bledsoe.
14. Brian Westbrook
Brian carried the Eagles offense into the Superbowl in Terrell Owen's absence, last year. Though undersized, he runs hard and knows how to pick up extra yards. He also has outstanding hands and moves. However, he is not a "between the tackles" runningback and the Eagles know that. Otherwise, they wouldn't be interested in Lamar Gordon (instigated by Buckhalter's surgery).
15. Ricky Williams
I don't have to tell you that had this been 2 seasons ago, or had this list been made last offseason, and Ricky was not a retired man at the time, he would easily be a top-10 runningback, and rivaling the top-5. But he did retire, and he is 10 lbs. underweight. Ricky has missed a year of football, and though I absolutely ate up what I saw in the Jaguars game, I have to see him perform a little more to know he still has it.
Honorable Mention:
Fred Taylor - talented, oft injured
Kevin Jones - quick, inexperienced
Travis Henry - built and runs like a prototype RB, oft injured, has "breakdown" games
Warrick Dunn - undersized, helped by former Denver OL coach
Stephen Jackson - unproven, has all-around game
Dominick Davis - gets more credit than he deserves, still very productive
Rudi Johnson - overachiever, not naturally explosive