Man, these guys you mentioned are both classic and classy. There are a few mid 70's guys in this group, but most of them played from late 50's to late 60's. I'm pretty savvy with all sports, specifically into the art of it. With 22 active position guys on the field, that is a lot of art. Part of that art is coaching scheme, talent, wisdom, experience, dome play, and then there is the frozen tundra.
As for Alex Smith, I'll just say grit. But he needs to retire based on the injury he sustain a yr or so ago. His style at quarterback is a disadvantage today. He's a pocket QB, you are a liability today if you are not an experienced, wise, savvy pocket QB. The guys coming in to bash your head are bigger, stronger, faster and that's just based off talent. Throw in a scheme and you are toast. The best pocket QBs in the game today; Rivers, Brady, Brees, Big Ben, Ryan, Rogers. Out of this list, Rogers should be the only one playing because he has a scramble along with his pocket presence. Scramble doesn't mean a run like some of the younger QBs do. Rogers got this figure 8 scramble move around the tackle and guard, sweet.