Yes, D&D has evolved into 4 basic types of characters, weapons guy, skills guy, arcane guy, and divine guy. But there are more to every class to mixing and matching it up aspects and making the percentage of what and what.
The fighter is heavy weapons. The rogue is the skill class. The cleric is the divine class. But the paladin is not simply a fighter/cleric because it is part weapons and part divine. Subsystems are a the wrong (read as lazy) way to make the paladin. A fighter/cleric and a paladin are two separate things.
A fighter has the basic adventurer aspects, basic combat features, advanced combat features, and some exclusive fighter stuff.
A cleric has the basic adventurer aspects, basic divine features, advanced divine features, and some exclusive cleric stuff. A character that has basic and advanced combat and divine features is a fighter/cleric.
The paladin has to be something else.
The fighter is heavy weapons. The rogue is the skill class. The cleric is the divine class. But the paladin is not simply a fighter/cleric because it is part weapons and part divine. Subsystems are a the wrong (read as lazy) way to make the paladin. A fighter/cleric and a paladin are two separate things.
A fighter has the basic adventurer aspects, basic combat features, advanced combat features, and some exclusive fighter stuff.
A cleric has the basic adventurer aspects, basic divine features, advanced divine features, and some exclusive cleric stuff. A character that has basic and advanced combat and divine features is a fighter/cleric.
The paladin has to be something else.