Quarterback is by far the easiest position to neglect in fantasy football. There are so many to choose from that it should almost be a sin to spend an early draft pick on one. These are the sleeper QBs that no one in your league wants to draft but will win you a title.
If you're looking for a safe pick at QB then Rivers is your guy. Last year Rivers played with a dreadful offensive line that was constantly shuffling players in and out. He also started the season without Antonio Gates who was suspended 4 games. Rivers also lost his number 1 receiver Keenan Allen midway through the season. Despite all of the terrible things that can happen to a fantasy player, Rivers still finished 12th among quarterbacks! The Chargers also look even worse defensively than they did last year so I expect Rivers to be throwing a lot after his team falls behind early on. Rivers can produce regardless of the circumstances that he's dealt. Get this guy on your team!
A lot of people have lost interest in Stafford after the past few awful seasons and they have good reason to. However, this year things have changed. Yes Stafford did lose his greatest weapon in Calvin Johnson but all throughout his career he's had only one real target to throw to and as Megatron got older we saw Stafford struggle to produce fantasy numbers. This year Johnson is gone and the Lions have added solid receivers to the roster. Things will be different for Stafford who will now be throwing to the likes of Marvin Jones, Golden Tate, Anquan Boldin, and Eric Ebron. Although none of these receivers compare to Megatron individually, they are all reliable options that will get the job done. The Lions also haven't improved their run game or defense very much so I expect the Lions to play from behind and throw a ton!
Ah famous Jameis, he's 6′ 4″ and 227 pounds of beast. Last year he started off slow playing without Mike Evans but then he really turned it on and impressed everyone. Winston finished off his rookie season 13th among quarterbacks while Marcus Mariota finished 22nd. Currently Mariota is being drafted many rounds ahead of Winston and it makes absolutely no sense to me. Take this young QB coming into his 2nd season incredibly late in your drafts and reap the benefits.