After much experimenting I found the following map generation works quite well:
Players: 7------------------Clusters: 7
Height: 60% ---------------Cluster Height: 60%
Radius: 42 ly---------------Cluster Radius: 20 ly
Minimum system distance: 4 ly
Home systems: Unmodified
This generates a map with following features:
- Map is not symmetrical and some clusters can contain stars that are far apart while others with close stars and some a mix of both
This makes for an interesting map where some races may have inherent advantage or disadvantage for their starting location. Life is never fair
- All the 7 clusters have correct geographical names and bubbles so the map doesn't look weird (some of the other map types can have random geographical names in the middle of nowhere which doesn't make sense). Not sure if this makes a difference with AI behaviour but I read in a few forum posts that it supposedly does?
- Each of the 7 races will have approximately 15 systems to colonise before clashing borders and fights ensue hence my choice of 105 systems. If you enjoy having more systems to settle you may bump this to 150 and the map also works quite well.
- 2 Nebulas don't seem to be too visually distracting while adding some colour to the map unless you get a ginormous nebula that blinds the whole map. Recreate