Woe, to be an Ice-ish race...

[Taera]

andres, some people plain like ice planets. not all people are gamey, especially not myself.
yes, ice may be disbalanced. but there is another dimension - if you can win on ice planets... well, woe to your enemies once you move to rocks or gases

[Andrés]

What I meant is that I consider the disbalance to be a bug.
If you can't get another colonization tech by trade or analizing captured ships you will be in disadvantage. Rock and Gas natives can also get another colonization tech quickly and keep their advantage.

[Phoenix-D]

Test game:
Out of 752 planets:
172 were Gas (22.8%)
215 were ice (28.5%)
365 were Rock (48.5%)

Same conditions, another test:
Out of 737 planets:
168 were gas (22.8%)
360 were rock (48.8%)
209 were ice (28.3%)

[Krsqk]

That would explain why I'm only finding 25% colonizable planets in one of my current PBW games (no trading). I knew there was a reason to take rock.

[Ruatha]

Originally posted by Andrés Lescano:
Ok I revised again my graphic and realized of the error I had made when counting moons.
Here you have it, more than half of the tiny planets are none atmosphere.

To answer the topic question, I made some calculations by multipliying the number of each size of planet by the number of facilities it gives and adding them.
Here are my conclussions:

Without Domes:
Methane-Ice 477.33 facilities (4.69%)
Oxygen/Hydrogen/C Dioxide-Ice 500.44 facilities (4.92%)
None-Ice 619.11 facilities (6.09%)
Oxygen/Hydrogen/C Dioxide - Rock 800.89 facilities (7.88%)
Methane-Rock 824 facilities (8.10%)
Oxygen/Hydrogen/C Dioxide/Methane - Gas Giant 854.22 facilities (8.40%)
None-Rock 928.67 facilities (9.13%)

Considering domes:
Methane-Ice 901.42 facilities (5.12%)
Oxygen/Hydrogen/C Dioxide-Ice 919.91 (5.22%)
None-Ice 1014.8 facilities (5.76%)
Oxygen/Hydrogen/C Dioxide/Methane - Gas Giant 1366.8 facilities (7.76%)
Oxygen/Hydrogen/C Dioxide - Rock 1471.8 facilities (8.35%)
Methane-Rock 1490.3 facilities (8.46%)
None-Rock 1574 facilities (8.93%)

The difference between Methane and other atmospheres is that they have 1 more small-rock and one less small-ice planet. Maybe a bug in sectorabilities.txt, it gives a slight advantage to methane-rock and a slight dissadvantage to methane-ice.

Advantage of rock-none is compensated by the fact that they'll have less non-domed planets when researching extra colonization techs (no none-gas giants), and that they will not be able to use atmospheric mod plants on gas giants for the same reason.

Note that gas giants are comparatively better if we don't consider domes.
This advantage is compensated by the comparatively lower number of domed facilities in large and huge planets.
Difference between atmospheres and none is also acentuated (still putting rock-none in first place above gas giants), since there will be no domed moons that make up a good part of the domed space.

So in conclusion:
The best combination in the early game is allways rock-none. That advantage goes away once extra colonization techs and atmosphere converters come into play.
Then best ones are rock and then gas if domes are allowed (as usual), if not gas and then rock.
Ice planets are always a large dissadvantage, none-ice is better than other-ice.

Still a good post.