A few thoughts on this.
While we have good memoryies of Palmer, he really wasn't a game breaker when he was in a "rushing" position. I recall most of his carries came from end-round runs, and very few from a direct snap situation.
If we look at last year as an example to work with, we had three running backs that averaged right around what Palmer did when he carried the ball. He ran the ball less than 100 times when he was playing for the Tide and averaged right at 6.5 yards a carry.
Here's what needs to be considered. Palmer, in '93, had about the same number of carries in that one year as he had in '91 and '92 combined. Why? Williams was the only player that was consistently getting the yards our three RB's had on average last season.
If we have a problem getting yards out of more than one running back next season, then I can see someone considering getting one of our athletes involved.
But, Arenas? I have to ask why considering guys like Maze, Hanks, Grant, Goode...I'm stopping there, but you know we could continue with a few more names before even get into the incoming class in August.
One other thing I believe you have to consider.
Avoiding a defender who is running full speed at you head on versus avoiding a defender who has the job that is based more on a pursuit angle as much as it is getting down field... - see where I'm going?