NPC reputation on faction join
When I join a faction, the reputation to NPC factions (maybe players as well) is reset to 0. At least, this is what the GUI shows. Now after doing some of those reputation "resets" on an official server, I realize that there is one NPC faction, where it is now "reset" to -1000 when I join a faction.
Seems the reset to 0 was misleading me, and there is an actual reputation that remains unchanged on faction join but is not shown by the GUI. The one faction might have gone < -500 (or < -1000) in the meantime although the GUI was always showing something > -500 and that "internal reputation" might be the reason why "GUI reputation" now shows exactly -1000 when I join somewhere.
Background: I find the NPC reputation system quite unbalanced, as the sum over all reputations can only decrease over time (for each job you gain some rep somewhere but lose even more rep elsewhere). As the GUI made me think of this "reputation reset", I continued having fun with NPCs despite that fact. Without any reset, I feel forced to not do any NPC jobs at all, which removes some fun from the game.