Jackson has tremendous physical skill but he needs work on his reads and comfort in the pocket. If someone who knows how to develop QBs, like McDaniels, got their hands on him he could be a top 10 QB in a few years, IMO. Jackson, right now, is vastly better than Cassel was when he took over for Brady and Cassel was looking pretty good by the end of the season, coaching and supporting cast count for a lot.
YouTube - Tarvaris Jackson Highlights
Hoyer probably isn't going anywhere but I think he's looked very good when he's played and would be a lot less risky than Bradford for Clausen, if the price was right it would be a good move.