When I was under 50 population I was able to have 5 administrators. (with colony management skill)
Next bonus was supposed to be at 50,
The message I received when I hit 50 read "3 bonus administrators next bonus at 80 population"
But, it seems I'm maxed out at 6 admins, plus the 3 I can administrate myself. It's impossible to hit 80 population without use of AI cores/administrators, what puzzles me the most is why did it say that I got 3 bonus admins but I'm still stuck at 6 total? or is that 3 (2+1) from base and +1 +1 +1 from population tiers bonuses?
3 colonies under my management + 6 admins = 9, 9 x 6 max population = 54.. I don't really want to go the AI core route but, I think having more systems, or -- all the systems under my control eventually would be a "end game" type goal, I don't see the point in stopping people from doing that as, quite frankly it's not imbalanced, I'm already unable to spend my money.
Total domination should be a thing, we don't have enough end-game things.
Edit: I suppose I could make some colonies semi-autonomous, but that seems lame too. I want to be England in Space.