Palffy would be second. In todays game, those two have the best scoring/+/- ratio and all around games.
Oh, if you have Nash in there then you should have Frolov as well. They are from the same start year and have the same amount of points. Niether or near tops in the league but since they are the two out of thier class who are improving significantly over last year (rookie) and you have Nash then Frolov with his same scoring and his +12 should be on the list too. I think anyways.
I'm using TSN's rule of thumb where you wouldn't trade a player who ranked lower than another (one-for one). Even though I think Thornton hasn't played well at all this season, I still have to vote for him. IMO he has as much value as Forsberg and wouldn't trade him straight up for any other player in the league including Forsberg.