This is a weird perspective. The middle planets can be approached in any order. And mods allow near-infinite variety - especially those that build on the platform of custom planets.

> there is only one way to do a thing and no room for a player to invent alternatives.

Sounds to me like you are caught up in trying to chase optimization and bemoaning the fact that there's only one optimal strategy. Do a no trains run! Or a no bots run. Or a 1000x science modifier run, or Lazy Bastard, or Death World, or... there are plenty of constraints, both programmed-in or self-imposed, that can push you out of the "standard" optimal strategy.

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.