Abstruse
Legend
"I could attack the evil thing with my longsword, but I think I'll just heal myself and leave my allies to rot." Enforcing roleplaying choices in class mechanics never works."I could drop a Flamestrike on your head but I am going to buff myself instead, just for the RPing heck of it" does not say Paladin. I think that is obvious. Therefore a cleric who happens to be handy in melee with a good martial weapon is not a great choice.
Then what does "say paladin"? They're getting physical buffs from a divine source. If they're X times per day, what does it matter if they're innate abilities or spells (which, again, have been called "prayers" in multiple editions)?A lesser argument is that standing around casting spells to get up righteously buffed up does not say Paladin either. I would not say such would necessarily be wrong, but it would be a lousy primary mechanic. Paladin-ness manifests directly in action.
Why? What is the difference between "I have miraculous seeming abilities given to me by my deity" any difference than "I have miraculous seeming abilities given to me by additional studies in arcane lore" as the Magic User theme? Put that theme on a fighter or a rogue and it still works.The other obvious option is Fighter with a theme and background. Is "I have miraculous seeming abilities given to me by my deity" does not sound like a theme or background. It sounds like a class ability.
So we're back to the basic question again - What exactly IS a paladin? If it's a holy knight in shining armor with a magic horsie and any variation isn't a paladin anymore, that's a specific build. If every paladin looks exactly alike, there's no reason to have even a theme to support it. If a melee fighter who has divine abilties, there's no reason to not do it as a theme. Plug a martial theme on a cleric or a divine theme on a fighter. If it's a warrior with a strong code of ethics, that's not even a theme, that's a background at best and should just be the backstory for the character. And you should never attempt to enforce roleplay through mechanics because it never, ever works. If it's none of those, then what exactly is a paladin?