By most accounts, Jason Taylor is a good guy to have on the field, in the locker room, and off the field. Even when I took jabs at him for his obnoxious comments about Jets fans, I always had a lot of respect for the work he did off the field. I remember many Dolphins fans were upset the team let him go for what they lost in the locker room.
This might be a point in favor for keeping him. If the Jets try to upgrade the outside linebacker position, it will likely mean getting younger. Having Taylor for a mentor could pay dividends. He could give the new guys tips on technique or how to attack a certain player. I know the coaches do this, but having another voice would help.
I am not sure this should or would be the only factor, but it might serve as something of a tiebreaker if the team is on the fence about keeping him around.