I don't have my comics with me, so I can't check my Golden Age omnibus and see who is in that comic. Could Timely have sold the rights to Charlton?
I was lumping the 70s characters into one Guardian of the Galaxy. Isn't Cosmic Ghostrider a joke character, like Gwenpool? I entirely blanked him out. But it seems odd to me that they left off THE first Marvel cosmic character, Silver Surfer. Granted, the 60s cover would be beyond crowded, but they went with the Inhumans, and NOT Surfer?
Though, I guess you could count Phoenix and Beta Ray Bill as sort of cosmic.