Make uranium only available on planets/moons instead
More specifically, make uranium only available on planets/moons in world files with planets, rather than stripping it from planets/moons. Worlds without planets should still see uranium generated in asteroids though.
This will drive players to the (currently) practically almost useless planets, rather than driving them into deep space in their search for uranium. At the same time, worlds without planets, possibly for performance reasons, will not be effected.