So, the terminology I’m using is less for genetic arrangements or how they got their powers or whatever, and more a rough generalization by generation/era so you can make assumptions about them.
|When I say…||…you should think|
|Deltas||Pulp heroes and “street-level” exceptional humans (Doc Savage, Batman, Captain America)|
|Gammas||Your average Bronze Age (’60s-70s) supers (Avengers, Fantastic Four, Justice League)|
|Betas||The grittier Iron Age of the ’80s (the various X-Men franchises, Punisher, Watchmen)|
|Alphas||Modern comics, a progression and amalgamation of the above|
This doesn’t mean that every Delta is an aging World War II vet, but that most Deltas are on par with those kinds of heroes: an exceptional human with a few super-senses, instead of a guy made of metal, a girl who can shift through walls, or a flying dude man of fire.
It starts to break down with Alphas; thanks to the internet, reprints, and retro-homages, just about any kind of hero can be found in print comics, leading to a melting-pot which combines elements of all of its forefathers. The “Alpha” generation is meant to reflect that, where any kind of hero is possible. Again, the first three are generalizations based on era, where the last one is a melting pot of the past done with modern sensibilities.