A few questions on your synopsis:
Why is Cam giving up his Green that he fought for?
Why would the Browns take Schaub when they have invested a good draft pick in Quinn?
Why would the Ravens take Schaub over McNair, who did pretty well last year, and Troy Smith, who is being groomed as the McN"heir" apparent?
Why are the Raiders trading their number one pick for Schaub?
Why would the Bucs want (yet another) QB?
I am not sure if you are oversimplifying the QB into a "plug and play" position or if you are underappreciating some of these teams, but I disagree on some of these synopses.
Look, the premise of my post was not to take into account the contract situations, what each team spent for the player, how many current QB's are on their roster. I know full well, that I'm neither an NFL coach nor an NFL GM, but I'm speculating and simplifying things by declaring that we're looking at each team having the straight up opportunity send their number one to us and our number one to them without cap concerns, draft picks, etc. Just potential production over the next three to five years.
So I'll answer your concerns:
The Dolphins got Trent Green with a fifth round pick as he was at the deadline for having to be cut from KC. He's productive but older than dirt. He's also like a candle....One good blow and he's out. The Dolphins would trade Trent "Methusela" Green for Schaub in a heartbeat.
The Browns aren't sold on Frye and took Quinn as their QB for the future, but there are serious question marks about Quinn's skills. Quinn will probably need at least part of the year to learn before he even takes the field and then let the horror show begin. Put Schaub behind their improved line (new OT, Steinback), Jamal Lewis, their recieving threats (Edwards, KWII), and their improving defense and they become competitive in the toughest division in the NFL. No playoffs, but in it until the last two or three weeks.
The Ravens got McNair because Boller couldn't cut it and was a bust. Their defense is the best in the league, but with Boller at the helm, their offense was so anemic, they couldn't make the playoffs. McNair helped them to a division crown, but he's a mobile QB who is aging. They'd trade because Schaub offers a better potential for success over 3 to 5 years. McNair is also an injury waiting to happen. Baltimore will contend again this year, but with Schaub, they'd contend for the next five. Anyone who would take Troy Smith over Schaub has sniffed too much glue. He could surprise, but no-one would rate him over Schaub.
The Raiders spent the number one overall on Russell, but he's at least a year away from really being able to help that team. His physical skills might make him a better QB than Schaub in five years, but over those five, they'll lose a bunch as he gets seasoned and learns the ropes. The Raiders would trade spots. Would you as a Texans fan take Russell straight up to lead the team this year? It'd spell at least three more years of losing.
Finally, the Bucs. They don't have a starting QB. Chris Simms has nevery recovered from having his spleen ruptured and then removed.
They've got Garcia who is on the downhill side of his career. Two years maybe? Chucky would take Schaub and send Garcia without a second thought. Don't even get me started with that Gradkowsky (sp?) cat.
The point is there are lots of teams who would like to have Schaub instead of who they've got, but circumstances get in the way. After the season, player's stock may rise or fall, but Schaub would give at least 13 teams a better chance to win than what they've got right now IMO.
Go Texans