I say this every time it comes up, but I think it is a point that is not be readily apparent.. It's not just the number of planets that can be colonized that matters, but also the number of opponents.
Simply put, Gigantic and Immense maps are unbalanced with only six factions, IMO. This symptom simply a reflection of the greater problem. But on those larger maps, if there were, say, 14 to 16 total factions (10 majors and 4 to 6 minors), I think a lot of complaints would be lessened. In fact, I'd bet dollars to donuts that people will start complaining that ideology will be far too hard to collect when more and more opponents are pumped into the game.
That's the problem with analyzing balance issues when everything isn't in the game yet. Yes, there will be a maximum of eight majors and who knows many minors provided by Stardock in the base game. But that's when Custom Factions comes into play. If one thinks there aren't quite enough major factions in a game, add them oneself while waiting for SD to make more official ones via DLC and expansions.
Even on a Huge map, six total opponents is probably not enough. I say that, because I am in the middle of a Huge map playthough (abundant/abundant/abundant), and I spammed out planets like they were going out of style. I didn't resort to any exploits like buying off ships from opponents, but I still round up with 82 planets after the colonization rush with everyone else in the 20s or so.
I still have 31 ideological traits to be unlocked (including the disabled ones).
No, I haven't built a single ideological building. But that's the point. Even after spamming pretty hard and colonizing something like 40% or so of the planets on a Huge map, I am still far from finishing out the tables.
Simply colonizing planets won't let someone get the whole table when there are a reasonable amount of opponents. Sure, it's a good leg up. But even so, one will need Random Events and/or Ideology Buildings to complete the tables.
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Now all of the above notwithstanding, I do think it would be a good ideal to let players adjust the "speed" of ideological growth via a game setting. Make it harder (or easier) to get the next trait. That way, people who this it is too easy (or too hard) to gain ideology will be happy. I just don't think having a setting tied solely to number of planets is a good idea without taking other factors into consideration.
