The Canton Screw-Job:
no Chuck Howley.
no Lee Roy Jordan.
no Drew Pearson.
no Ralph Neely.
no Ed too tall Jones.
no Harvey Martin.
no Everson Walls.
no Darren Woodson.
Look, let's keep it real. Every team has their gripes with players being overlooked, or not put in. Drew Pearson not being in is a travesty. Same goes for Chuck Howley.
As for the rest of the list above? Lee Roy Jordan was a terrific player, but he was an All Pro selection just once in his career. He played during a time where he was probably the fourth or fifth best middle/inside linebacker of his time. He wasn't better than Dick Butkus, Ray Nitschke, Joe Schmidt or Jack Lambert. It's arguable that he wasn't better than Tommy Nobis. It doesn't diminish him, but I don't think he's a Hall of Famer.
Same goes for Ralph Neely. He did make the All Pro team three times, but he wasn't even the best tackle on his own team. Rayfield Wright was better than him. He isn't even considered a glaring omission for the Ring of Honor. Very good player, not a Hall of Famer.
Too Tall Jones was a good defensive end. Played a long time. Made All Pro once. Not in the Ring of Honor. Not a Hall of Famer.
Harvey Martin has a case - he was the Defensive Player of the Year in 1977, a Super Bowl MVP, and made the 1970's All Decade second team. He was the leading sacker in team history until DeMarcus Ware passed him 30 years after Martin's retirement. There are two knocks against him - one is that he made first team All Pro only once. Second is that once open handed blocking was legalized in 1978, his sack production decreased significantly. He's also not in the Ring of Honor, which doesn't help his case. To me, he's borderline.
Everson Walls was a true ball hawk, and a very good player. He led the league in interceptions three times, and was in the Pro Bowl 4 times, and a first team All Pro once. That being said, he also gave up a lot of big plays, and for as productive of a ball hawk as he was, he was never considered a shut down corner. Again, he's not in the Ring of Honor. I think he's in the same category as Jordan and Neely - very good, but not a HOF player.
Darren Woodson absolutely should be in, but he won't get selected. The reason why he should? He revolutionized the safety position by being a player who was quick enough to cover receivers in the slot, large enough to be a force in run support and as a blitzer, and a terrific special teams player. He was a three time first team All Pro safety. The reason why he won't? The same people who vote for the HOF select the All Decade teams. In the 1990's, Ronnie Lott was selected over Woodson for the safety position. Lott played half the decade, and was a shell of himself in the 1990s. Sadly, this oversight will prevent him from getting in.