If you like the sci-fi theme, Satisfactory is a fun builder but it is mostly building factories (obviously).
Empyrion is a survival builder. You build not only bases but ships, hover crafts and space stations. You have to find resources on other planets so you need to progress enough to get off world. It is integrated with Steam Workshop and has a creative mode so you can build and test all you like. It will scratch almost any builder itch you might have.
There are others like Creativerse which is a Minecraft like builder but with better graphics and different mechanics.