Changes:
* Base district cost is now multiplied by the era of the tech or civic required to produce it;
* Costs increase per copy at the rate of 1/6th the new base cost for 1 per city districts, and 1/12th for multiple per city districts (i.e., neighborhoods).
With harbors and commercial districts at 60 + 10 per copy, it was just too easy to spam cities with both, creating 2 trade routes and giving a trade destination that gave +4 production just from those 2 improvements alone. Add that to 60 + 10 industrial districts and production quickly got silly.
With the new formulas applied to the base districts (they're applied by SQL updates with formulas, so should also work with district mods), the current version gives:
Code:
DistrictType Cost Increase Per Copy
DISTRICT_HOLY_SITE 60 10
DISTRICT_CAMPUS 60 10
DISTRICT_ENCAMPMENT 60 10
DISTRICT_HARBOR 120 20
DISTRICT_AERODROME 360 60
DISTRICT_COMMERCIAL_HUB 120 20
DISTRICT_ENTERTAINMENT_COMPLEX 120 20
DISTRICT_THEATER 120 20
DISTRICT_INDUSTRIAL_ZONE 180 30
DISTRICT_NEIGHBORHOOD 300 25
DISTRICT_AQUEDUCT 100 16
DISTRICT_ACROPOLIS 60 10
DISTRICT_BATH 50 8
DISTRICT_HANSA 90 15
DISTRICT_LAVRA 30 5
DISTRICT_MBANZA 90 7
DISTRICT_STREET_CARNIVAL 60 10
DISTRICT_ROYAL_NAVY_DOCKYARD 60 10
I'm still experimenting with balance issues and whether this is a good idea at all.
This does get rid of the spend 1 turn to start a district to lock in the cost exploit, btw--a started but unfinished district still counts for the increase per copy cost.