^This. It’s kinda boring that one city of NPCs is friendly no matter what, and others are hostile no matter what
There should be a system that NPCs are more interactable, for example:
Level of relationship: Hostile, Stranger, Indifferent, Friendly.
Black hand faction: Hostile towards relation stranger or below
Killing/Enslaving other faction NPCs grants temporary relationship bonus that will reduce with time
Hostile towards all other factions gives a big permanent (as long as you stay hostile to all other factions) relation bonus.
Help them in a fight (random encounters that different factions clash, or help them raid other player base) grants temporary bonus
Indifferent relation will make them not attack you, friendly will grants you option to purchase some random listed profession thralls from other tribes, since they enslaved them
Religion factions:
Dogs of the desert (for Jhebbal Sag)/ Heirs of the North (for Ymir)/ Dafari Cannibal (for Yog) etc
More Set, Mitra and Derketo faction locations need to be added
Hosile towards stranger or below relation.(Except Mitra and Set follower faction, only hostile in hostile relation)
Do their religion thing (harvest using religion tool, use altar crafted items etc) grants relation bonus
Help them in fight (random encounters) grants temporary relation bonus
Unlock altar, having built altar (only give bonus once), wearing religion gears give permanent bonus
They should be the only place to hire high level priests once they become friendly, and trade them with religion item for zeals.
Relic Hunter:
Hostile only when hostile relation, and relation is dropped when they are attacked, otherwise act pretty much the same way
And except for their capitals and religion trainer location, all other spawning points (camps and ruins) may have invasion from other factions and may be taken over. The alert will notify all players on the server so they may help out and try to take the location for their favorite factions