It is an interesting case study though as most of the "surefire" pocket QBs have been pretty good. Almost all of the "run first" QBs have failed which is why Lamar Jackson is not going to be drafted at the top of the draft. 2004 was the standard with 3 great QBs that changed franchises.
The NFL has finally started to figure out that running QBs don't work there. Being mobile is great, but you have to win in the pocket.
Aaron Rodgers should have been in the top 15 but fell. In 2011 I feel that teams "reached" for QBs that weren't that highly rated.

2018 has 4 QBs that I would call "surefire" pocket QBs. Now Allen was not very good in college and Mayfield doesn't have the build of the prototypical NFL QB. My personal rankings would be as follows:
Darnold-Has everything you are looking for although needs to clean up some mechanics
Mayfield-Has been a phenomenal QB, undersized but accurate, with a strong arm and smart
Rosen-I was never wowed by him in college as BYU always had his number (I saw other games as well)...he looks the part and has great mechanics
Allen-Perfect NFL QB body with excellent athleticism for his size. Ben Roethisbergeresque. Accuracy and competition a concern. Needs a great QB coach.

The NFL has proven that you can find a good QB anywhere (Warner, Romo, Brady, Prescott, Wilson...etc), but more often than not it is predicated on a first round QB.

2017-Mitchell Trubisky-Incomplete
Patrick Mahomes-Incomplete
Deshaun Watson-Incomplete but great start
2016-Jared Goff-Still Incomplete, but good sophomore season
Carson Wentz-Barring an injury prone career will be a star
2015-Jameis Winston-Has been disappointing, but as a 3 year starter I would not call him a bust
Marcus Mariota-Has been very solid and help to turn around the Titans
2014-Blake Bortles-He just got a new extension so hard to say bust, hasn't been very good though
2012-Andrew Luck-Has been good when he is playing, currently injury status unknown
RGIII Had a great rookie season and then fell flat...as the #2 overall pick he was a bust
Ryan Tannehill-Has shown flashes of brilliance but been mostly mediocre
2011-Cam Newton-Former MVP has been a very good pro
Jake Locker-Bust
Blaine Gabbert-Bust
Christian Ponder-Quite possibly a bust, but married Sam Ponder
2010-Sam Bradford-Has been a good pro when not injured, done enough for me not to call him a bust
2009-Matthew Stafford-Has been phenomenal
Mark Sanchez-The buttfumble Sanchize started very good but has fizzled? Bust? Debatable as the Jets got some good results early with him.
2008-Matt Ryan-Excellent
2007-Jamarcus Russell-Bust of Epic Proportions
2006-Vince Young-Was a very average pro QB
Matt Leinhart-Bust
Jay Cutler-Best of the three QBs, has had a long career in the NFL
2005-Alex Smith-Very solid pro career
2004-Eli Manning-2 Superbowls
Philip Rivers-Great Career
Ben Roethlisberger-Great Player with 2 Superbowls
2003-Carson Palmer-Very good career
Byron Leftwich-Had some solid seasons, but not worthy of a top 10 pick
2002-Derek Carr-Bust after being sacked a billion times
Joey Harrington-Bust
2001-Michael Vick-Good NFL career