This poster by John Buscema and Joe Sinnott for the 1975 Marvel Convention features all the stars of that era.
Not only do the big superstars look great, but so do the “B” players (Ka-Zar, Luke Cage Powerman, Shang-Chi, etc) and the Marvel monsters (Ghost Rider, Frankenstein, Dracula, etc). There are even two licensed characters, Conan and Doc Savage. What a diverse world the 1975 Marvel Universe was! Nuff said!

Photon Torpedoes: DC Comics, Games, Pop Culture Blog
I've had this large, original convention poster, framed, for many a year.
While not the all-time "best" thing in my collection, it IS special because it's one of the few items that features both; Dr Strange AND Man-Thing (my two big faves).
You are correct, however.
Every character, no matter if "A-list" or "D-list" is drawn dynamically by the late, great John Buscema.
~P~
PTOR