We're fine without Cotton - Long and Reed are good. We're fine without Marlowe - he's like 5th on the depth chart anyways.
Rex - this goes without saying but we need the guy. I don't need to tell you guys about how his running skills are important, but also from a depth standpoint - we need our starting RB to be there to shoulder the load. Ameer would do fine filling in, but there's nobody behind Ameer to fill in some backup role voids.
Heard? Still think he wil end up being the better back by the time they both graduate. Cross looks promising as well, not saying we dont need Rex, if this was 2011 i would go ahead and throw in the towel without Rex, this year we can manage without him, but of course we are a better team with Rex.