Eh, I mean you've got guys like Earl Campbell, Jerome Bettis and Christian Okoye to think about too, in addition to your mentions of Brown and Simpson. Also remember Eric Dickerson was 6-3 220, was basically Bo before Bo, and Walter Payton ran people over at a much higher clip than Bo ever did. Not even trying to bash on Bo, he was amazing, but you're overrating him a bit here.
That said, 98 SPD, 92 ACL, 89 AGL, 89 STR, 93 CAR, etc., it would be really hard to overrate him, frankly. Just lay off the 99s and you'd have a hard time messing it up, OP.