One thing I'd note is that I'm still not sure how connecting stars in a different way affects their output, maybe the tutorial could give a hint for that (unless figuring it out is part of the game).

The 2D version had a tooltip which broke down every element that affected output and tooltip which listed all modifiers affecting the claim cost of stars. I didn't figure how to show that kind of breakdown in a 3D map. Formulas are the following "outbound power = inbound power + local production". And "Output cost = distance / 100" and "Output = outbound power - output cost".

Also, the tutorial screen is missing that space advances turns, it's only on the itch pages's description.

I had a feeling that I missed something small in tutorial screen.

Gameplay-wise, my only problem would be that once you or the AI are in a losing situation, in the back-and-forth struggle phase I mentioned before, it's pretty much impossible to come back and the game just "plays out".

Yea, I the game is currently intentionally fast and decisive since there aren't that many subsystems at play yet. Although, I do want to add more AI's with different grand strategies, since the current AI's grand strategy is to collect the most valuable stars and bee-lining to your capital.

Also, did you also know and use maximized window?