Say Fyron, in your Quadrant Mod, you have a lot of moons with atmospheres... Doesn't that put None breathers at a disadvantage, since they no longer have more breathable planets, while they still can't find any breathable gas giants? How about increasing the proportion of planets that have no atmosphere - or did you already do that and I didn't notice?
(goes through solar system to see if it's reasonable to have more airless planets... Mercury, no appreciable atmosphere. Venus, carbon dioxide. Earth, oxygen (for SE4 purposes). Mars... questionable, either oxygen or none. Jupiter, hydrogen. Saturn, hydrogen. Uranus, methane. Neptune, methane. Pluto, none. So there, three out of five non-gas planets in the solar system have no atmosphere!
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