Fighting ability+religion+oath+whatever feats and fighting style add the flavor you want. Done. Now we can get rid of Paladin. They're just fighters.
Spellcasting+books+school of magic+whatever feats and spells add the flavor you want. Done. Now we can get rid of wizards. They're just...
Three things.
1st edition Cavaliers "traipsed" around in dungeons as you put it all the time. And if there's not much place for a shining knight in 5e, a significant portion of Paladins should bugger off.
I've DMed, played, or sat in on hundreds of games of 5E since it was released. Still a...