Yes, actually I am. While Asche is certainly not going to be a great player he may have a future as a bench or role player.
Nava is a 34 year old player with back to back .560 and .590 OPS seasons. He was better before that, but that is getting to be a while ago and he is on the downside of his career. If he has one more season like that he will be out of baseball.
Asche is 26 and has been a slightly below average hitter, ,.684 OPS for 4 seasons, with last season being his worst at .635. He will probably get a few more chances, even if he has to go to the minors.
Basically, we would be lucky to get a guy with Asche's history for Nava in my opinion.