Well I don't know about you guys but this was educational for me, no doubt. I looked up sooty palominos online and they are quite pretty! Smokey, almost.
As I was on the search to find more pics this afternoon (this search took me under the bed in my files and animal papers) and I found my bill of sale and notes.
I had jotted down that this equines sire was a palomino, and his mother was a red dun. So it seems that everyone is correct in their color diagnostics? His parentage says he's got the dun gene, but you are right that his color more resembles the smokies.
Loved everyone's input - you guys know your stuff!