... Paladin Danse is dead. Can you beat Fallout 4 without joining a faction? No. This step requires you to side with a major faction, but your allegiance can still be changed. There is no other way to end the faction war. You could continue playing the game as long as you like ...
Here are all 46 Archetypes in Metaphor ReFantazio and information on how to unlock each one in the game. This includes the Prince and Royal Archetypes.