Shardstone
Hero
This is literally just the Warrior with subclasses. Why not just play the warrior and let it take a subclass at the same levels of Fighter?I'm not wholly convinced that the champion's simple niche could not be in some way preserved. Some of the additions should be skill or tool related, or some can be basic passive benefits, which the Champion needs as much as anyone else. You could give the main class 3 options, including a simple suggestion, a tactical one, and one to help allies. Any players who want to keep it simple just picks the simple one.
What's even the point of having the Warrior and the Fighter? Sidekick classes are meant to be simple classes for either NPCs or people who are just kind of vibing and dont' want to worry a lot. Why in the world does the Fighter also have to be simple? The Warrior literally is right there. It makes no logical sense in any way, shape, or form to say that the Warrior and Fighter BOTH have to be the "simple martial class."
Not to mention the barbarian is the simplest class in the game. You literally just say "I rage and attack" for 20 levels.