I wanted to play on a finite planet but still be able to build a megabase, so I increased the map radius setting to 100,000. But the size of Nauvis didn't change at all, it's still about 20 chunks in diameter.

The setting only applies to newly generated map, so you’d need to delete Nauvis and start again.

Yes, I meant that the size of planets doesn't change when I start a new game. I also tried disabling all mods other than Small Space Age to see if other mods are interfering with it, but Nauvis is still the same size.

Also idk if it's intended but on Vulcanus, demolishers spawn on the space tiles. It's funny to see them floating in space.

Ah thanks, seems that setting broke recently. Fixed in 2.1.1.