I'll probably end up having to make a mod for this, but I had to ask... Why is "Commerce" and "Military Base" considered "Industry"? Seriously, "Commercial" and "Industrial" districts have been two different things since early 90's SimCity. And "Heavy Industry" is doing the production of ships, guns, and supplies, not the "Military Base". I already find the "Industry" limitation terribly heavy handed, arbitrary limitation that doesn't make sense.
There's better ways to limit development in a manner that just isn't silly. I mean the maximum spaces you can have on colonies was 12, and one had to be used by the "Population & Infrastructure" and other by the "Spaceport" (for all practical purposes). So, you were left with 10 to work with total. Maximum colony size is 10. So... How about a colony slot per population size? Now some would argue that'd technically allow for 3 industries right off the bat... Which is correct. Something I think should be allowed as it is risky and limiting already by the game existing mechanics. Think about it, that means no Ground Defenses, Patrols, or even an Orbital, and it's expensive to setup that many industries at once... Especially when you are going to leave them wide open. It think it handles itself.
Also lore wise, this is exponential growth with each population bump. So, on a planet with billions of people... They only have 4 industries and that's it?