Based on QB history, there are very specific paths the Jets should travel to build a Superbowl winner.
Realistically the Jets will probably kick the tires on Micheal Vick, investigate a trade for Alex Smith, and then wrangle in some vets to challenge Sanchez if all else fails, like a Matt Moore or Jason Campbell. Probably drafting a mid round QB (not wanting to pay a big salary to a first rounder), and hoping for a Russell Wilson-esque gamble.
But based on history the only free Agents they should be targeting are Alex Smith, Micheal Vick, and Jason Campbell. Now honestly, I'm not a huge fan of any of these guys. The Jets O-line is too porous for Micheal Vick to stay upright and Jason Campbell is a shell of himself (as witnessed in his start in place of an injured Jay Cutler). I have less reservations with Alex Smith, but he is a system QB, and the Jets do not have the personnel to accommodate his skills (at least not at the moment).
Superbowl QB Analysis
Now the history I speak of is this. I went back over the last 30 years, and of the Superbowl winners, only 8 Quarterbacks didn't finish draft day with their original team (worded to fit Eli's trade in). Of those 8, 3 were 1st rounders (Dilfer, Plunket, Williams, Young) and 2 were second rounders (Farve, Brees), Kurt Warner was the only anomaly, going undrafted.
Its a pretty telling pattern. To build a Superbowl winner 22 of the past 30 QBs to win were drafted by their team. Of those 22, only 3 (Brady twice, and Jeff Hostetler) weren't first round picks.
For me that makes this offseason a very special one. If the Jets were to reach out for a Matt Flynn, he would have to buck the trend as only 4 QBs taken later than the 2nd round have won the Superbowl in the past 30 years (Brady (6th), Hostetler (3rd), Johnson (9th), Warner (undrafted)).
The stats suggest the best path is probably either to 1) stand pat, and bring in a veteran to push Sanchez, like a Matt Moore, or 2) draft a QB in the 1st or second round.
1. Sticking with Sanchez
Now I'm sure sticking with Sanchez is a scary prospect for most. But lets take a look at the numbers by year.
We'll leave the analysis lite for Sanchez's first year. He finished with the most interceptions in his career 20, while having the fewest attempts in his career (264). But he also had the most yards rushing (106) for 3 TDs, this was the year he missed a game due to injury to his knee and Joe Girardi was brought in to teach him how to slide.
Year two was a very safe year, but progress was clearly there. His attempts were up, as to be expected with a full year of Braylon and Santonio, and LT in the passing game. He had his best TD to interception Ratio (20 - 13), as well as least fumbles lost, a ridiculously low single fumble lost to 8 fumbles overall. Stability was probably the biggest boost to his progress here, the only major change to the starting lineup from the end of the previous year was LT swapping with Shonn Greene.
Year 3 is generally considered a flop for Sanchez because of their record and lofty playoff goals. But it was actually his best statistical year. He accounted for 32 touchdowns (6 rushing) and finished with his best passer rating 78.2 %. Consider that this was on top of him being sacked an awful 39 times (making his 8 fumbles lost, compaired to 1 the previous year more understandable). Mark actually progressed each of his first three years increasing his passer rating and touchdown count.
Year 4 he regressed, but some of it may very well have been coaching. In each of his first three years, Mark rushed for at least 30 attempts and 6.4 yards per game, for over a 100 yards, and and at least 3 touchdowns. In his fourth, only 22 attempts for 28 yards, a 1.9 yard average and 0 touchdowns. You would then think that he was tossing it more, but Marks attempts were the lowest they've been since 2009. His interceptions were the same as the previous year, 18, same as his fumbles lost (8 in both), but his touchdowns were down more akin to his 15 game 2009 season (13 in '09, 12 in '12).
For me the numbers actually make me wonder if the reason his stats went down were more because of Sparano's use of Tebow in short yardage than anything else. 3 Interceptions in Year 4 came on the first play Mark returned to the field after a Tebow package, it brings questions about if he was rushing for short yardage and goal line situations like in his first 3 seasons if Mark's regression would have happened at all. If we take those 3 interceptions out and substitute them for 0 yards rushing, that would have been his 2nd lowest interception total of his career behind only Year two's 13. The Touchdown drop is to be expected with 10 Receivers playing throughout the season (Holmes, S.Hill, Kerley, Schilens, Turner, Gates, J.Hill, Gilyard, White, Edwards) and 7 Backs (Greene, Powell, McKnight, Conner, Hilliard, Bell, Grimes) there just isn't time to develop chemistry with that much constant change. A good example of this can be found in the first three weeks, the receiving core of Keller, Holmes, Hill and Kerley didn't even last one game, but Mark posted a 123.4 Passer Rating (2nd best of his regular season career). Down Keller, but still strong for two more games, mark posted 5 TDs, 3 Ints, the fewest sacks over a 3 game period of the year, and only 1 fumble.
The other thing to consider is, if the rumor of the next GM being told they need to be able to work with Rex for at least the next year (it should be noted he has two years remaining) are true. It might be all the more reason to just wait and clean the entire slate. Because if Rex is out and you stood pat with Sanchez, that means the season came apart, so the draft pick would be high allowing for a high caliber first round QB. As well as Sanchez's contract extension having a non-guaranteed base salary in 2014-2016, so he can just be cut.
2. Draft a QB early
Now this is the favored method among most fans, understandably so. I think the part that might give you pause, is the possibility of a miss. Sanchez was a miss in 2009, but the Jets past has actually favored taking a first round QB in terms of longevity at the position. Since the Merger, the Jets have taken 4 QBs in the 1st round, and were pretty hit or miss, in terms of statistics.
Richard Todd was a bust, there's no getting around that. In 1980, he set the record for throwing at least one interception in 15 games in one season. His best season came with the NY Sack Exchange, but his stats were poor all around, culminating in 1982 going to the AFC Championship game and throwing 5 interceptions in a 14-0 loss.
Ken O'Brien had over 25,000 yards in his career, led the league in the lowest interception rate for 3 years (1985, 1987, 1988), had the highest QB rating of '85. His biggest knock is mostly being taken before Dan Marino. Since neither got a Superbowl, we'll call this a split.
Chad Pennington is a push. His stats were good. Of QBs with at least 1500 pass attempts, he is the NFL all-time leader in career completion percentage (66%), he was also the last Jet QB to lead his team to the AFC East title. But injuries were really what will be remembered, as evidenced by being able to win Comeback Player of the Year, twice.
And then we have our current case with Mark (who's stats I've already broken down).
It makes it a big question mark of can the Jets break the QB issues that have plagued them for years and draft "the right guy". The choices (if all the QBs are on the board) for the first round are probably to decide between Geno Smith (WVU) and Mike Glennon (NC State). Matt Barkley has fallen, and the Jets aren't going to take another USC QB with question marks. Personally, I'm a big Geno Smith fan, but depending on where (or if he does at all) Chip Kelly lands, he might tab Geno Smith as the guy to run an NFL version of his Spread offense in a place like Arizona or Buffalo, who both pick before the Jets. With him gone Mike Glennon might go to the other QB needy team, leaving the Jets with neither of the two highest ranked Rookie QBs available. The Jets would need to reach, or take a QB in the 2nd round to give themselves the best statistical chance of Superbowl success with this Quarterback.
We all have differences in opinions on how this should turn out. As a fan, I would be fine with alot of directions. Mark returning with Braylon resigned, healthy Santonio and a first or second round Running back, might be potent, or a swap for Alex Smith. Matt Flynn could be the next Matt Schaub. A Rookie QB could be the next Luck/RG3/Wilson. But the numbers favor just two paths, and going with Mark and Rex, for one hot seat year is probably the best long term solution if the 1st round rated QBs are off the draft board by the 9th pick.