- yes, 7 or less minor factions. i have heard that you might trigger a invasion war if all systems are full, but i haven't seen one in the bubble.
- the expansion range is a strange thing. @dommarra made a good cause arguing that the algorythm works in cubes instead of a bubble, as it is easier to pull systems from a database that way, and it works along differences of coordinates. anyway, longest direct expansion i have seen without investment is 29,36 ly distance ... i still can't get my head around it, as we jumped several possible systems closer by. might have been a bug, too.
- the maximum range after investment is between 45 ly and 55 ly, as factions don't expand from robigo to almagest (55 ly distance), but expand between maia and HIP 19072 (45 ly) after investment.
Useful to know, thank you. The one I want to go to next (if I choose to expand again) has 7 MFs so I might play the long game and go there first and force some other MF to retreat and create room for a new entrant, and then give a go at expansion (aiming for it) because at 8.8Ly it is the closest of all populated systems - 'my' MF has expanded into the #2 and #3 by distance already.