I mostly play on tgstation’s european server Terry, which often gets up to 100 players in the busy hours.
I know exactly the kind of anxiety you mention when it comes to having to learn a new role. That was partly why I also had the idea of installing a server locally to tinker with the mechanics in, which fortunately tgstation actually makes very easy. My problem then is that I only have like 10 minutes alone on the station before the power runs out, and I have to go set up the solar panels to continue my experiments. Turns out being solo crew on a space station isn’t all that easy.
How would you decentralize physical infrastructure like roads, rail, power lines, sewers etc.? Someone will need to be responsible for maintenance, and you can’t exactly switch out which sewer is connected to your house in case you’re unsatisfied with whoever is running that show. I’m imagining 20 identical roads running in parallel from A to B so people can choose which one to associate with. And a hundred different internets cramming the already limited electromagnetic spectrum we have because there’s no central authority to regulate them.