Timing is good econ. We need a deadline or we will be at this forever.

The sand box needs to model reality, but it will still be abstract to a degree.

Movement I think is set as "Risk style",

your points c, d, e and f all need to be captured and addressed in essence.

I think your three rule sentences cover that. My only issue with them is that they state that in a civil war all money is spent FIRST on the civil war requirements.

I think it should be AFTER non civil war requirements are met.

The clear point you make and that I see as vital is this;

"It does not have supply, but we can abstract from that here as it is not crucial to the determination of civil war. Some rules for how to "share out the cake" when the faction fights itself are crucial to the determination of civil war and do need to be considered as there is nothing in CAs programming that covers a faction fighting itself."

That's what we need to address is a KISS format. Once distilled your three rules get very close to dealing with the above issue.

That should be the focus.