Another idea I had (which was already used in the Disney movie, Treasure Planet) is to have wooden ships flying between planets and stars. If certain alien species are capable of magic, then they can achieve low-tech space travel.
Now for something weird. I have always had dreams of finding stores and restaurants in weird places. In my dream game, I plan on having the in-game stores be corner stores or convenient stores, much like in Earthbound or Pokemon, but given the schizo tech in this science-fantasy universe, you would have basically modernized convenient stores in medieval, old-western, or even pre-historic styled buildings. So there will basically be rustic, wooden buildings with modern beverage fridges inside. You can even have a cave with one room of the cave being a modernized convenience store.
So basically just have old-style buildings with modern (or futuristic) appliances in them.
Speaking of caves, I was thinking about having an alien race that builds everything in hollowed out caves, maybe in cliff-sides (like the Puebloans), or in completely underground caves. They probably might even hollow out asteroids, moons, and dwarf planets to make space stations. So imagine going inside a cave and seeing apartments, hotel rooms, restaurants, stores, etc.
So I thought of a fictional currency for an alien species where the "money" is actual a form of energy that is stored in the body and can be transferred from one body to another. From a video game design stand-point, it's brilliant because it's an in-universe explain on how the characters are able to carry that much money.
I have ideas for power sources that these civilizations might use. There could be a fruit that is very electric. You know how some people make lemon batteries? Why not have a fruit that can actually be used as a practical power source and have these aliens farm them?
Or maybe free energy could exist in this universe. Many people believe that the Pyramids of Giza were actually ancient powerplants that tapped into energy from the ionosphere or the electric current flowing between celestial bodies (if the electric universe theory is to be believed). We can have alien civilizations using such technology. It fits perfectly with the combination of low and high-tech that this science fantasy universe provides.
@coolboymew Oh yeah, I forgot, but they would take the place of the Jedi in my science fantasy universe.
@coolboymew Also, the witches would be 100% alien and I'm not talking about human-looking aliens.
@vokainen099 @coolboymew I got AI to generate them. I should've included "steampunk" somewhere in there.
@vokainen099 Different races could have different magical and technological abilities. More technologically advanced species may have little to no magical capabilities while the more primitive types could have more. Some races might even have biological castes that determine their magical capabilities.
Gas Giant planets can have floating islands or even continents in them, kind of like the main setting of Skies of Arcadia.