Earth 69 is a Hypertime variant of Earth where the world is a bit of a brighter, more "classic comics" or "four color" place. It's not all fun and games, though. Sometimes the struggle gets serious. Villains still try to take over the world. Even in the Super Friends series, there were dark stories--but they were the exception, rather than the rule.
Effusia is a world of fun superhero antics much like the Silver Age, where brightly-colored heroes fight iconic villains and are generally expected to win...though not before going through some really wild ordeals first!