We’re making modular assets and using procedural generation to fill the world, take a look at NMS way of going about it, they did have a budget but it wasn’t really used on the programming and modeling, that was already planned out and doable with the lower budget they had initially. Even so our world is not nearly as big as any of those games, we have confined planet levels and a single solar system (our solar system) not 1:1 scale. If you go about it in a thought out way it’s totally doable! Also we already have the worlds in place, unreal engine 4 needs no modifications to get that to work, just some workarounds here and there - this issue is the only thing we have not been able to work around yet.