This series is the first other media adaptation of Superman that takes partially into account the major revisions to the character by comics artist/writer, John Byrne in his 1986 post-crisis relaunch. The most notable elements used are that Clark is no longer Superboy in his youth and Lex Luthor is a villainous business owner armed with a kryptonite ring to ward off Superman.
Wonder Woman's appearance is based off her comic book reboot under George Pérez. This includes her flying under her own power rather than via the invisible jet.
Ruby-Spears was acquired by Warner Bros while Superman was in production and was finished under Hanna-Barbera's roof.
When Toy Biz released the DC Comics Super Heroes toy line in 1989, it's depiction of Lex Luthor was heavily influenced by the appearance of the character in the Ruby-Spears' Superman series.