They did a good job mixing the science fiction and western genres--always a feat.

Tons of action, but as LL always said, the pulp serials (the background of the new movie)stressed action. I don't even know the original author, only that there were lots of tales and a sequel to the new movie is already planned based on more of the tales. Seemingly this would have been pulp fiction competition for LL.

Overall plot for anyone who doesn't know: just after the Civil War, a gold hunting Confederate fugitive finds a device that teleports him to Mars where he becomes a savior to some large insect-like creatures.

In retrospect, it is too heavy on action and little else and LL was right to balance this with characterization and setting.

Did LL ever get any closer to sci-fi than The Haunted Mesa (really fantasy since there's no scientific reason for the other plane of existence--only myth and magic)? Anyone know? Maybe a sci-fi Lost Treasure?

This would probably have been too easy for LL since there's no history or culture or terrain to study--you could just make that all up!