I am on the fence with Ryan. I am not sure what he will be like as a head coach in this league. One thing to remember is that he was loaded with talent in Baltimore(Reed, Lewis, Suggs, Ngata, etc.). Having that much talent can make anyone look good, just look at Cam Cameron coming to Miami from the stacked Chargers offense.
Now, he may turn into the next great big time coach, but I just don't know yet. He is a bit of a loose canon, and if things start off on a sour note, watch out.
I honestly don't know if firing Mangini(who improved the team by 5 wins this season) and hiring Ryan was a move that was a no-brainer. Now if they fired Mangini and hired someone like Cowher or Holmgren then I could see it as a no-brainer