Now, if you ask me (and, of course, you DIDN'T
) The size distribution should be more of a bell curve around the medium size...Fewer Huge & tiny, more medium. Tinies should have less of a chance to have an atmosphere of any kind, and, Ices should have a higher percentage of having an atmosphere of some kind (usually whatever the ice is made of). Rocks should be evenly distributed & Gasses should always have an atmosphere (as they both already are).
Also, I really like randomization...I'd like to see a completely random button...where all the planets' sizes, atmospheres & makeups are ALL compelely random. You could conceiveably pick a Gas/Hydrogen race and end up with your home planet being the ONLY one in the galaxy.
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Spyder, Chairman of the Arachnid Consortium