How about E E "Doc" Smith's "Lensman" series?

Well, of course, Lensman is such a setting.

is the origin version of space ghost pulpy enough?

The Adventures of Captain Zoom in Outer Space (1995)

Flash Gordon actually took place in the present, not the future! But still a great setting. I would love to play in something like the Sam Jones/Timothy Dalton/Melody Anderson/Ornella/Max von Sydow/Chaim Topol/Brian Blessed movie version. That would be so much fun.

Armageddon 2419 A.D. by Philip Francis Nowlan. The original novella the created Buck Rogers. Modern copies are usually both novellas in the two part story: Amageddon 2419 A.D. (1928) and The Airlords of Han (1929).

 

Great books and not what most people think of when they think Buck Rogers,

This, both the books and comic strips, are two (or one) of my favorite pulpy science fiction settings. Unfortunately, although I've written a bunch of Hero material around it, I've never gotten a group of gamers to play in it.

If you're interested in additional source material, try GURPS Lensmen (2nd edition if you can find it, since they added additional material to it)

If you're interested in additional source material, try GURPS Lensmen (2nd edition if you can find it, since they added additional material to it)

It's on my bookshelf. (I love this stuff)

I was saddened to find that there was not an electronic version for sale at Warehouse 23, but such is life with licensed products.

Do you have the Rocketship Empires 1936 books John? They're no longer available for sale on DriveThru, but there were at least four items (all I have, anyway): Rocketship Empires Core Setting, Setting Book In Fury Triumphant, Ship Focus book The Gunslinger Betty, and Starship Compendium 1.

Do you have the Rocketship Empires 1936 books John? They're no longer available for sale on DriveThru, but there were at least four items (all I have, anyway): Rocketship Empires Core Setting, Setting Book In Fury Triumphant, Ship Focus book The Gunslinger Betty, and Starship Compendium 1.

I've got the core book, but none of the others. This actually came up in a random convention discussion this weekend - and none of us were able to remember the name of it. Just about drove us nuts until someone not part of the discussion threw the name at us.

Oddball idea: what about a post apocalyptic Earth? The heroes could be from an advanced city state, but most of the planet could be overrun with radiation devolved mutants, monsters, resurrected dinosaurs, savage tribes, lost and sunken cities, a patchwork of radiation badlands and resurgent super-flora, and the like. You could have sky-ships, a rival city run by a Ming the Merciless type, and ray guns. Think Flash Gordon meets an amalgam of pulp tropes. And, you don't even need rocket ships. Unless you want them, of course. 

Oddball idea: what about a post apocalyptic Earth? The heroes could be from an advanced city state, but most of the planet could be overrun with radiation devolved mutants, monsters, resurrected dinosaurs, savage tribes, lost and sunken cities, a patchwork of radiation badlands and resurgent super-flora, and the like. You could have sky-ships, a rival city run by a Ming the Merciless type, and ray guns. Think Flash Gordon meets an amalgam of pulp tropes. And, you don't even need rocket ships. Unless you want them, of course.

Thundaar the Barbarian! The show even had a high-tech city in a bottle!

 "Rocket Age " (already mentioned) is fun. I have, from time to time, both run and played in a campaign. The campaign features Leigh Brackett as an NPC (an adventurous journalist on Mars who has decided that the P C's "make good copy").