Thanks for this!
It's funny. Instinctively I knew that 8 major factions would be far too few for an Insane map, so I made 8 others to go with it (they were just "alignment flipped" versions of the pre-existing ones). But even with 16 majors and who-knows-how-many minors, I was finding Insane maps far too empty of competition. Sadly I'm just not up to creating 56 other custom factions to "properly" fill out an Insane map. So I'm gonna have to wait for the community to get cranking on other majors for me.
For comparison, here are the values for GC II (as of Twilight):
1 sector = 225 tiles (15x15)
Tiny: 2,025 (9 sectors [3x3])
Small: 3,600 (16 sectors [4x4])
Medium: 5,625 (25 sectors [5x5])
Large: 14,400 (64 sectors [8x8])
Huge: 32,400 (144 sectors [12x12])
Gigantic: 72,900 (324 sectors [18x18])
Immense: 108,900 (484 sectors [22x22])
Each GC III map size has more tiles in it than the corresponding map size in GC II. However, that might be a little deceptive because of how the maps are generated now. Mostly due to nebula/gas clouds and black holes taking up space on maps. Even with the tweaked planet generation in Beta 5, I still think it might be slightly (very slightly) under the generation rate of GC II. So while there ARE more tiles. there's also more things to fill them up.