Why is it never generating a planet bigger than earth?

[shavius]

I have tried several planet classes, doesn't matter which I select, in the later planet generation phase, there is never a planet bigger than the earth appear, whether in terms of gravity or radius. Is it caused by some of my setting or it is meaned to be designed like this?

[Elver]

It's settings. I get 1g+ fairly regularly with a number of different classes, but I know off the top of my head that I've gotten a fair number of 3g planets with Cerebus.

[zgrssd]

Planetsize depends on Mapsize. As each Hex as a fixed scale, only more hexes can make a bigger planet.

[Zanotirn]

Actually planets can easily roll bigger radius than Earth, just not by much. Earth's radius is aroud 6370 km, while I've seen planet radius go to around 6.8K. Gravity can go significantly higher, though it depends on planet class. Hydra tend to be lightest (not counting moons and planetoids), never going above 1g for large planets; Boreas, Limos and Medusa can go to around 1.2g, Seth to around 1.4g, Siwa 1.6g, while Cerberus and Morgana have a weird situation (not even sure it's working as intended or not) where they can roll up to 1.4g and then from 2.41g to just under 3g (but not in the 1.41 to 2.4g range).

[Catasteroid]

Here is an image of the planet data table in the debug interface while in-game, the size of each planet class is defined by the PlanetSize value which is formatted as <Minimum>@<Maximum>, as the surface area of the planet increases the volume increases by the square of the surface area which makes the mass (and thus gravitational pull) skyrocket above current planet sizes, it's especially bad for planets with high heavy elements percentages such as Cerberus (140-220% heavies) and Morgana (150-200% heavies). The actual planet size and surface area/hex size is determined by the chosen planet size option with some variation, I believe the strict size definition (currently only for for unclassified planets) adjusts the target size.
I get the feeling that logistics AP costs, aircraft, and other features were tailored with the current specific sizes in mind and going beyond that starts to stretch things outside their intended scope.