A semi-random line of thought I had while getting some exercise today.
What id Gas Giant Generator (possibly soon to be a build only once building), Solar Orbital Generator (usually build only once per supply group), Black Hole Power Generator (1 per supply group) and Hyperspacial Dam (1 per supply group) all added infrastructure to the planets in the system. This way you could have higher infrastructure in places off of your capitol.
Lets say something like the following:
Gas Giant Generator: +10 Infrastructure to planets in the system.
Solar Orbital Generator: +20 Infrastructure to planets in the system.
Black Hole Generator: +30 Infrastructure to planets in the system.
Hyperspacial Dam: +10 Infrastructure to planets in the system.
This gives a maximum possible infrastructure bonus, with stacking of +30 in one system, with tech bonuses bringing it to max total of 100 infrastructure per planet in the system. For the sake of keeping the numerical constraints it might be necessary to restrict these buildings from being built in the capitol system.
Also since the Transformer comes after Energy Force Structures, which will give all planets at least 40 infrastructure, I'd say it should cost 20 or 30 infrastructure.
Now if we make most buildings cost infrastructure, maybe excluding the shipyard upgrades, you should be able to still peruse a relatively centralized strategy. Lets say that most buildings each cost 5 infrastructure, with a shipyard, that's room for 18 buildings. If my count is correct there are only 17 or 18 other permanent buildings in the game, and not all of them are going to be built at the capitol, or together. For instance the Xenoresurection Lab the Collective Thought Network and the Concentration Camps are not likely to be placed at the capitol, while the functions of the Bioterror Projection Base, Planetary Starlane Drive, Spacial Distortion Generator and Stargate are all filled by the Transformer.
A likely current build for a late-game capitol ecumenopolis planet would probably be the following:
|Automated History Analyzer||-5|
|Enclave of the Void||-5|
|Imperial Entanglement Center||-5|
|Species Interdesign Academy||-5|
This allows for growth at a rate of 1.5 per turn. Meaning that the capitol can afford to be rather Trantor-like, with every building having an influence cost.
Edit: it also occurs to me that if we leave N-Dimensional Structures giving +10 infrastructure, and have Force Energy Structures give +10 infrastructure we could have both Asymptotic Materials and Architectural Psychology also both also give +10 infrastructure, giving us 4 bonuses of +10 each.
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