Charles, Johnson, McCoy, Sproles, Best (when healthy) have all been productve very recently. Spiller had a very solid stretch. David Wilson was drafted in the first.
I'm not arguing that small backs can't be successful in today's NFL. That's obviously not the case. What I'm saying is this: Just because a player fits a rough "type" does not make him as good as the best from that type.
Pead and Hillman are undersized jitterbug types. That doesn't automatically mean they are as good as the best undersized jitterbug types in the NFL.
Most of the successful guys you named have special qualities.
Sproles is a unique animal. He was an absolutely insane college player, but his severe lack of height had him pigeon-holed into a gadget player role for most of his pro career. His cutting ability and vision are off the charts. It's evident in his college highlights. And the production suggests rare talent as well. He rushed for 1300+ yards for three years in a row in college, averaging over 6.0 YPC during that stretch and nearly topping 2000 rushing yards as a junior. The guy was a first round talent downgraded for one simple reason: he was extremely short. Pead and Hillman are average height for a pro RB. Not parallel cases.
Best, Johnson, Charles, and Spiller are sprinters with rare burst. You're talking about guys with 4.2-4.3 type of speed. The kind that makes your jaw drop. Apart from being on the light side, Pead and Hillman really don't stack up with these guys from a physical standpoint. They run in the mid-high 4.4 range and lack special athletic qualities. That's probably why they slipped to the 2nd-3rd round while Best/Johnson/Spiller were all recognized as first round talents.
The same more or less applies to David Wilson. Athletic freak of nature.
The closest comparison is McCoy. On paper, Pead and Hillman are pretty similar to him. They were very productive in college, they were drafted in about the same spot, and they have approximately the same dimensions and measurables (McCoy was a disaster in pre-draft workouts). I understand why so many people make this comparison, but it doesn't really jive with my own subjective observations. Hillman and Pead
don't really pop off the screen for me in the same way that McCoy did. I know some people won't agree with that. It's just my opinion and I don't expect everyone to find it convincing.
Without the special athletic qualities and without the eye-popping highlights, Pead and Hillman are just productive college players with good draft pedigrees. Getting that 2nd-3rd round stamp of approval from at least one pro scouting department is a big feather in their cap and the main reason why I still take them seriously as draft prospects, but for me they aren't guys who belong in the top 10 of a rookie draft, and certainly not over first round talents like Floyd and Wright. I think they're more likely to be the next Lorenzo Booker than the next LeSean McCoy.