Walker's stats are very similar to Denson's, and he likely would have surpassed all of them had he not questionably left a year early. And it's worth noting that Walker did not enjoy the Holtz/Moore offensive lines that Denson had for 2 seasons, nor the rush-heavy scheme. Both guys were elusive playmakers who never failed to show up when it mattered.
I think Denson had a very unique vocal leadership quality that inspired his teammates. Walker was more reserved, and I don't know that he could carry a team in the same way, so 2007 would have been interesting.
I do agree that the lack of a 5th gear is what holds Denson behind J.J. or C.J., but I can't ignore its absence.