[Astromancer]

Try this idea.

Superheroes show up on this world in the late 1930s. Unlike most fictional superhero continuities the actions of the superheroes significantly change the world. By the late 1960s Earth was entering TL9 with supertech.

Though the 1970 to 2090 period large numbers of people left the Earth to settle in deep space mainly on easily terraformed planets. Note: this means easily terraformed by a TL9 society with lots of powerful supers to help.

After 2090 a series of brutal wars rendered most of the Earth uninhabitable for several centuries. The refugees of the 2099 to 2115 period were more than 90 percent of the survivors of these wars.

Due to the actions of certain powerful cosmic beings, for a indeterminate time period supers will be rare and weak. The quid pro quo for this was Earth's foes would be fated to impotence for the same period.

The many settled worlds developed in relative, but not absolute, isolation. Cultural divergence was commonplace.

It is now 2368. The planet Augusta, settled from the USA and its allies and a stable social democratic society, has suddenly had a burst of supers. This is seen as a warning of danger. The planetary government is sending out exploratory expeditions to both seek diplomatic conections and gain understanding of any possible threats.

Augusta is an early TL10 society. Assume most human settled worlds are either mature TL9 or early TL10. As many as two fifths of human settled worlds are at lower tech levels either form cultural choice or social disruptions of varrious types.

The PCs would be a supers group with the expeditionary ships. Basically superpowered redshirts to protect highly skilled diplomats, and first contact specialists.

More later..