I'd say 4e was it's own thing. It is high level magic but put that stuff into rituals as a party resource.
Fighters in 4e are surprisingly mundane (minus Paragon Path and Epic Destiny) with a few exceptions that aren't really that crazy. They mostly attack with weapons, mark, and inflict conditions.
The difference of course is that Wizards were nerfed. They no longer have in-encounter mechanic avoiders and have to play within the same system of HP attrition. They do have more permissions than the Fighter -- elemental damage, summons, walls, teleport, etc. But the gap is narrowed in effect so it doesn't feel so bad.
Careful, if you talk about how great 4e Fighters were, someone is likely to bring up how "Come and Get It" was mind control...
Honestly, 4e's magic level was fairly tame compared to 3e, and by design. Most Powers only impacted the game for a single turn, "save ends" effects were generally worse than "until your next turn", and Rituals took a good chunk of time and money...and money was a secondary xp track. Most magic items were fairly mundane in their effect; one of the best boot items was the low-level Acrobat Boots that let you stand up from prone as a minor action! There were precious few open-ended effects; almost everything did exactly what was printed on the tin. This turned out to be a double-edged sword; on the one hand, it helped the game be better balanced mechanically. But it turns out that what a lot of people expect from D&D is not mechanics, but PRESENTATION (as MegaMind would say)!
They wanted evocative descriptions, deep lore, and things that inspired one's imagination. They wanted free license to be creative with the use of their abilities, and DM's wanted to feel like they could make ad hoc rulings on how Power X interacts with Situation 38C.
WotC made the mistake of thinking that the players and the DM's, left to their own devices, would create flavor- this, I think, is what Micah Sweet's arguments upthread boil down to. D&D is a game of imagination, FIRST.
If the rules don't spark one's imagination, they're so much bland mush to a lot of people. See, I myself am the type of person who can generate my own stories and lore, but I do admit, I am a lore junkie. I miss the old 2e/3e setting books full of interesting tidbits about settings. And I do appreciate how even a game like GURPS manages to fit in a few evocative bits to make someone go "Hm, now that sounds interesting".
Mechanics, even well written ones, don't make a character or a setting beyond "I want to play Class X with Subclass Y" or "The Tortles are a major race in my setting".
Unfortunately, what continues to baffle me about 5e is that, while there certainly is a lot more room to negotiate with the rules set (and boy are there a lot of corner cases), the game feels a lot less focused on description and lore than it's predecessors. Even the art comes off as kind of bland; I can point to many examples of 2e (and a few 4e) art pieces that made me go "oh man, I want to do something with THIS", but to a degree with 3e and to a greater degree with 5e, the art just makes me go "eh."
And yet, it remains very popular, despite feeling (to me) like a perpetually unfinished product. Even it's default setting has barely any info on parts of the world beyond a single coastline!
Back to the point at hand, while I fully agree that flavor for a class is what you make of it, the questions remain:
What will excite people to play this class? Cool abilities?
Is this just the Warblade/Swordsage all over again? An awesome idea that was largely rejected by the community?
And again, thinking of the Warblade, can a mythic martial really coexist with the Fighter, without people thinking that it's a "Fighter replacement"?
If you make a fantastic fighting class that's more in line with what casters do, what's it's niche? The game already has fighting-men and casters. Will it really feel unique, or just another flavor of what we already got (a big problem with the casters already, IMO).
And are we just doing an end run around AD&D style magic items, which were supposed to patch character classes in the first place by making new abilities something you went out and acquired, not merely handed to you (thus making the idea of going out and adventuring exciting?).
