I think the thing that really made factorio fun for me was deciding early on to NOT look at anyone else's designs online. Having the "correct" or "most efficient" answers handed to you removes the design part of the game and turns your base into a carbon copy of everyone else's base. I spent days figuring out how to make loops with train signals that would allow a train to spin endlessly in a circle at full-speed waiting for the path to become clear. I could have just looked up how to do that, but then I'd get no sense of accomplishment.