The system for moving between planets is locked down. It is rockets or nothing. And that system is deliberately designed to defeat scaling. What really killed me was the message saying I was only allowed one of a specific key building on each planet. That was very anti-factorio imho. As I said above, as an indi developer moves forwards they add constraints to focus and guide progression. I simply do not want that. So I disabled all the planet stuff and play like it never existed.

That restriction is needed in some way to prevent that building being a way of teleporting stuff across the planet. They did relax this in 2.1 and allow you to build extensions to that building where you can add inserters and use belts/trains.