http://www.spotrac.com/nfl/buffalo-bills/lesean-mccoy/
LeSean McCoy signed a 5 year / $40,000,000 contract with the Buffalo Bills, including a $13,000,000 signing bonus, $26,500,000 guaranteed, and an annual average salary of $8,000,000.
Until the Bills are set with a franchise QB, they need to go all in with the run game with McCoy and Iupati. That will free up the passing game to a point.
Crabtree and Iupati are both hitting the market and La Canfora of CBS Sports reports that the team could also look at cutting Ahmad Brooks or Vernon Davis.
http://www.sportsworldreport.com/articles/45101/20150302/49ers-rumors-frank-gore-michael-crabtree-vernon-davis-mike-iupati-out-in-2015-darnell-dockett-target-without-justin-smith-ahmad-brooks-return.htm
The Bills will need 4 QB's in camp in case of injuries. I would think another FA veteran would be better so the coaches can focus on EJ and not a project this season.
I would not spend big money on Revis. If he were the final piece of the puzzle to win a SB then sure.
The Bills have higher priority needs and extensions to do first.
The defense is in good shape as long as they extend Dareus.
Focus has to be on the OL , and hope EJ is the right QB , or it could take a long time to replace him.