I love Bo Jackson, but to think he's the in the top 15 of all time when he played for such a limited time is crazy. You can't just put him ahead of guys like Thurman Thomas, Curtis Martin, Shaun Alexander, Jerome Bettis etc. Now if you want to make the argument for most talented, that's a different story, but there are many other running backs that had better careers.
I agree that many had better careers, but I am basing this list and all my others on talent and legacy equally. If Bo had played longer, he would be top 10. If this was based on pure talent he would be much higher. If this was based on pure legacy, he would be much lower. I decided to meet in the middle and put him at 14.