I think a cool quest would be killing a weapons dealer with Good and Evil variants evil variant could be find able in the hidden tavern or wandering around while the good could be found by himself on a ship
Good Variant
"Can you help me track down a black market dealer? he is supplying dark wizards with dangerous weapons and needs to be stopped, I tried myself but he used a smoke arrow and I lost his trail.
And the evil variant would say something like “This master smith is giving to good of weapons to the magic council letting them capture my boys. If you stop him I can grow my group again and you will be rewarded”
The fight itself would be relevant to the enemy of weapons master as the mini boss would use bow and arrows, throwing daggers, shields, spears, swords, maybe have some Armour? and when red health would use a smoke arrow and shoot the ground in a attempt to escape though if this is to hard to script it could be simplified
As opposed to having them be a vendor NPC, perhaps they could be an NPC that supplies the vendors. That way, the vendors themselves still have their stock. It’s just that their supplier is gone lol.
I think instead of killing shopkeepers and other npcs, it’d be cool if there were quests that required you to go eliminate a convoy/patrol of several high level npcs (not minibosses but stronger than mc guards or bandits) of the opposite faction. For example a good version of the quest would be “Could you help my squad ambush a convoy of bandit traffickers? They’re smuggling high tier magical gems and need to be stopped!”