I found the government simulator spreadsheet lacking in various ways. For one, it has no way of understanding the in game situation. If a hostile alien species is attacking our forces, there is no way the senate would disallow research on weaponry or construction of new warships. Unless it's been updated to include such things in the year or so since I tried it out, it still has issues like that.

It's part of why I'd like to see some sort of additions to Aurora. In the very least, I'd really like to see government departments similar to the OP's idea that actually have impact.

for a system to be eligible for CMC spawning, it must have at least one colony with a population of at least 10M.
does this only count surface population? or does Ark module population count?

2. I don't see any tech I can research to create a Sector Command. Where is it hidden?

2.  Is Improved Command and Control, I think in Logistics but it could be construction

Confirming that it's in Logistics rather than Construction / Production.

1. Does water in the atmosphere do something special? I'm injecting some for good measure...

Water vapour in the atmosphere is part of the water cycle and shows up based on hydro extent, temperature, and total pressure; you can control hydro extent of a body by adding or removing water vapour with terraformers. Below -28C hydro extent and water vapour freeze solid and out of the atmosphere respectively, above +100C the hydro extent boils off and exists entirely in the atmosphere as water vapour, and between the two you'll have some vapour in the atmosphere and some on the ground as hydro extent with higher total pressure resulting in higher water vapour partial pressure.

You may still find different values than -28C (I've also seen -17C, -18C, and -27C, but Titan just melted at -28C) from older sources but that is the v2.5.1 temperature at which ice sheets spontaneously melt and begin to evaporate into the atmosphere as the water cycle takes over. Some of how water vapour, liquid water, and solid ice move about can be found in the change log: https://aurora2.pentarch.org/index.php?topic=12523.msg155204#msg155204

Questions, always questions!

1. Does water in the atmosphere do something special? I'm injecting some for good measure...
2. I don't see any tech I can research to create a Sector Command. Where is it hidden?

I have often wished, especially in light of the advanced government system that Geoffrey has in Antimatter, that Aurora had some sort of government system that you could select. You could choose from the vague standards of authoritarian, democratic/parliamentarian, monarchic/imperial, and oligarchic. Each would have customizable government departments that provide certain bonuses that diminish based on sector distance. The democratic ones would have elections and a bicameral congress (senate from planets, representatives from population). Oligarchic would have a selection process for some sort of triumvirate or whatever.

Each would, of course, have it's benefits and drawbacks. Authoritarian and monarchic governments would maybe have reduced loyalty (e.g. much higher demand for PPV and garrisons), while democratic and oligarchic would require approval of certain actions (such as declaring war, political parties that you must appease by meeting their demands, etc.). Unhappy pops would rebel and form a new empire of their own design. Meanwhile, Authoritarian might have an increase in certain types of labor, while democratic might have improved financial and perhaps things like throughput of spaceports and the like.

Obviously, I haven't fully thought it out. It's just something I'd like to see at some point.