I agree with much that has been said here.

• It's nice that ruins and villages are no longer complete dead zones, but they're still obstacles, which seems to clash with their argument against anomalies with penalties. If they can#t be treated as low-level borough, then they should at least provide some other bonus (+2 Industry from the labor power of the minor faction, and +2 Dust or Science from ruins)
• Tying approval directly to boroughs is a terrible idea, because it results in optimal layouts.
• I'm not fond of tying district levels to connection rules anyway, since that will, again, lead to optimal builds. I've been in favor of a manual upgrade system for a long time. That could also serve to differentiate the factions: While the Necrophages would get cheap extensions for sprawling hives, the Wild Walkers might get cheaper upgrades instead, creating compact cities producting a lot of Dust, Science, and Influence, but refraining from covering the entire natural landscape.