The Human Target
Adventurer
I voted option 3, No. Why? Because a character introducing themselves as "Hello, I'm Bob, I'm a fifth level Paladin who can attack twice and I also know how to Lay on Hands! Who wants to adventure with me" is stupid... I hate when a character is role played and introduced as their class. Characters should be whatever their profession or background is. So unless your class equals whatever your profession is (Bard, Ranger, Monk, etc.) then you should go with a more specific explanation.
Paladin = Guardian of ________, Knight of the Temple, etc.
Rogue = Pickpocket, Cutthroat, Con Artist, etc.
Fighter = Mercenary, Sellsword, Gladiator, Knight, etc.
"I'm a former soldier in the King James army. Once I served my contract I became a sellsword and soldier of fortune." sounds a lot better than "I'm a fighter!"
I get what you mean.
But you can be a Sellsword without being a Fighter.
You can be a Pickpocket without being a Rogue.
A Knight of the Temple could be a Fighter or Cleric instead of a Paladin.
Those terms don't actually answer the question of your character's very specific game world abilities.
I don't think it's odd that the people in that world would have terminology to explain those things.