Of all the things you listed the only sure thing is McMichael.
Chambers has skill but disappears to often. If he has another average season its not going to put you over the edge.
Booker is nice, but has been average since 02.
Boston was once dominant, but has been riddled with injury (roids) since 01.
Ricky...he could be a force, but does it warrent taking PT from you're 2nd overall pick for a guy who quit the team and who is, realisticly, coming back for financial reasons?
Ronnie Brown...jury is out on him, he could be very good, but we won't know until the season.
The O-Line, who knows? Houck should help, a year together will help, but they were horrible last year. You don't go from horrible to "best in the league" because of a coach.
Obviously everything could fall into place, but to think that one of the worst O's in the league is gonna be the best is silly.