What if the map would come with pre-generated idols (similar to Irminsul) enabling to build sort of a one-way Charter Stone in their vicinity (e.g. within 100 tiles). Anyone who learn a specific Charter Stone can use a Sublime Portico and a Thingwalls to travel to that Charter Stone. No travel between Charter Stones. Make that charter stone more expensive to build. Also, it would be interesting if a Charter Stone would generate specific random buffs at random time for a day or few, chance of doubling quality in forging, or harvest an extra onion

In short, I see that charter stones would help socially and trading.