I don't know if this is a good idea, but I'll throw it out there - what if sector size was determined by your admin cap? So you could put together a sector yourself, with a penalty in sectors that start or grow larger than 100% of your admin cap (maybe with an exception for sectors that are only one system). This would mean that if you raised your admin cap, you could possibly add more systems to an existing sector, if it wasn't already more than 75% of the limit. I figure this could make raising your admin cap feel a little more worthwhile early game, and lets you design your sectors yourself but puts an intuitive limit on the size of any one sector.
Just to explain with an example - consider you had an admin cap of 50, and you had 3 systems:
1 with no planets - I think that's 1 toward your admin cap? Let's call it 1
1 with 1 colonized planet with districts - the system in total contributes 35 toward your admin cap
1 with 1 more colonized planet, but this one is smaller - it's only worth 15 admin points
You could add the first and second sector which contribute 36 combined toward your cap, or you could add the second and third but that would be exactly 50 - as soon as either planet built a new district or you added another system, you would be over the admin cap and would get a penalty (maybe toward crime or stability). In theory, you could then decide to enact decisions, pick a governor or build buildings to counteract the penalty, instead of breaking your sector apart, or just eat the penalty if you expect to get a higher admin cap soon.
In the last game I played kind of a balance of wide and tall, and my empire size wasn't more than 3 or 4 times my admin cap, so I figure this will play out to encouraging somewhere between 3 and 4 sectors unless you are going wide.
.png){kind=avatar}
(no mods)
