AtmospheresAtmospheres should be able to be set in the manner of Pressure. (It would be complicated to program Separate layers and composition)
So like this:
<Atmosphere>
[ Density:(ower limit=0.000001 kPa)] {Presets: (Earth: 14.696 psi) (Mars: 0.145 psi) (Venus: 1300 psi)}
OblatenessNext to Rotation Period there should be an Oblate Scale.
[Oblate: (Min 0.0 Max 1.0)] {Presets: (Sphere: 0.0) (Saturn: 0.1) (Line 1.0)
(For Reference, Saturn has a 10% Oblateness)
(Earth is almost perfectly spherical)
(100% Would be a straight line)
This is a work in progress.
If you don't understand what i mean ill try to do a bit of photoshopping.