I think where all of this comes in focus is with the Champion Fighter. This is the most vanilla version of a class that you can get, set at the lowest power base in the game. It's good at swinging a sword and that is all it is pretty much designed to do. All other subclasses and classes are upwardly mobile in options, abilities and power. It is geared towards the gamer who just wants a no-nonsense experience to fighting monsters without having to track maneuvers, spells, or any other sort of resource beyond hit points.
Where the problem is that when folks attempt to add to the overall fighter's repertoire, this subclass holds the design space hostage. "Can't do that, it's too supernatural," is the general cry, and thus the fighter gets stuck in plate, holding a shield and swinging a sword - and not doing much else.
I am not for the craziness that we saw in 3.5E's Tome of Battle, but it is time to drop the shackles of the Champion Fighter. The class isn't even allowed to reach olympic-level abilities let alone the mythical abilities of stories and legends. There still needs to be that basic Champion Fighter for those that want a straightforward character, but its abilities need to be better than simply swinging a sword three or four times in a row. The greatest difficulty is to give the Champion Fighter those needed abilities in a way that doesn't require a player's mental load to remember the smorgasbord of options available to them, and simply just "works" (I can't tell you how many times I've had casual Champion Fighter players fail to use Second Wind simply because they forget they have it).
And do it in a way that does not marginalize the Ranger further (whose already lost his wilderness and tracking specializations to letting everyone in on those once specialized abilities), nor overshadow the Barbarian or Paladin.