Quarterback is the easiest position to improvise at in typical 12-team leagues, so you should really only be stashing developmental quarterbacks if they are high upside like Griffin or Kaepernick in that format, but in 16-team (or larger) or 2-QB formats, developing quarterbacks can be a very productive activity.
Robert Griffin III III, WAS - Even if you only think there’s a 1% chance he’ll bounce back, the reward in that scenario is very good.
Colin Kaepernick, SF - He’ll never have the passing potential Griffin has, but Kaepernick in a Chip Kelly system is worth looking into in fantasy leagues, and he could end up with Chip next year.
Jimmy Garoppolo, NE - His second contract two years from now will likely be with a team that gives him a chance to start. Long term stash.
Garrett Grayson, NO - The Saints could undergo great upheaval this offseason and leave Grayson as the likely heir to the quarterback job unless they find a better plan.
Drew Stanton, ARI - Stanton is a free agent and could be looked to as a bridge to a young quarterback or stopgap starter. For deep leagues only.
Brett Hundley, GB - This one will require patience, but like Garoppolo, Hundley comes with a likely shot at a starting job on his second team. He has fantasy upside as a runner, too. Will require long term patience, best for formats with taxi squad.
David Fales, CHI - The path to starting for Fales via a Cutler flameout has not come to pass, but I’m still a fan of Fales anticipation and aggressive mindset as a passer.
Sean Renfree, ATL - Matt Waldman favorite, ‘nuff said.
Ryan Nassib, NYG - There has been little to no buzz about Nassib out of New York while he backs up the ultradurable Eli Manning, but there’s probably at least a team or two that would give him a 49ers Gabbert-level interest when he hits free agency in 2017.
Jordan Cameron, MIA - Cameron was a bust in Miami and should be released because of his hefty price tag. He is still one of the best raw physical talents and most accomplished players at the position, not to mention he’s only 27.
Crockett Gillmore, BAL - This one might be obvious, but I get the feeling he is not getting the respect in the fantasy world that he should be getting as a prospect on the rise.
Jace Amaro, NYJ - Amaro is pure receiving tight end and he’s a good fit with Chan Gailey. He was probably forgotten after his shoulder injury put him on IR.
Luke Willson, SEA - Don’t assume that Jimmy Graham will be back next year (see also: Cruz, Victor). Willson could start in an offense that is looking vibrant in the passing game again, and he’ll be a free agent in 2017. His size/speed/athleticism combination shows some untapped potential.
Will Tye, NYG - The undrafted free agent has shown surprising speed and ball skills for a thickly-built tight end. He could push Larry Donnell for the starting job in 2016 and Tye isn’t close to his peak yet.
Jesse James, PIT - James doesn’t look sensational as a rookie, but he has progressed to competent and he happens to be in one of the best passing offenses in the league. If Heath Miller is in the December of his career, James could be the new gun in town in 2016.
Dwayne Allen, IND, Coby Fleener, IND - Fleener is the more accomplished receiver, but Allen has the higher theoretical ceiling. The problem is that Allen’s injury history might make him damaged goods anyway. Both will be free agents next year.
Zach Miller, CHI - Miller is new on the scene, but he’s actually 31 years old, so don’t expect a lot of shelf life. Martellus Bennett is probably out of Chicago next year and Miller is a free agent, although Chicago was the organization that stuck with him through two contracts and will probably want to stick him again.
Darren Fells, ARI - Fells is just getting started in his NFL career, but he isn’t young at 29. Still, he has showed good ball skills from his basketball background and he has been a downfield weapon. The Cardinals offense magnifies the value of the passcatchers, so if Fells is more of a full-time player in 2016, he could surprise.
Niles Paul, WAS - Remember when Paul had taken over the starting job from Jordan Reed? He'll only be 27 next year and he can make it as part of a two tight end attack. Reed has never been the most durable either.
Erik Swoope, IND - The former basketball player is on the practice squad right now, but with both Dwayne Allen and Coby Fleener hitting free agency next year, Swoope could swoop into a decent-sized role in an Andrew Luck offense.
Demetrius Harris, KC, James O’Shaughnessy, KC - Harris is a basketball convert and O’Shaughnessy looked very natural as a receiver in limited duty this year. Travis Kelce’s rookie contract expires next year, so either could be tabbed as his replacement if his price tag is too high.
MyCole Pruitt, MIN - The prospect of playing in a Norv Turner/Teddy Bridgewater offense isn’t nearly as exciting as it was a year ago, but Kyle Rudolph still looks like an old 26 and not deserving of his big extension, so opportunity could come in the future.
Cameron Brate, TB - Brate looked very promising in his bid to stick with the Bucs after getting a chance with Austin Seferian-Jenkins sidelined by a shoulder injury. The 24-year-old showed good hands and ball skills, and he’s going to play with one of the best young quarterbacks in the league. Seferian-Jenkins blocks him, but his durability record indicates that Brate will get more chances to shine in the future.