Epic Spellcasting, Automatic Quicken/Still/Silent/whatever Metamagic Spell, and others are epic for one reason: by those levels, there's no longer rocket tag but GP-02 Atomic Bazooka tagging. And even then, martial characters simply get "a boost" compared to spellcasters whom essentially get "I Win several times" buttons with Epic Spellcasting. By that level, feats should essentially provide martial characters with the ability to imbue any weapon they choose with the attribute they want, gain DR 15/epic and adamantine and good and that it scales highly per level, get spell resistance as a joke, and others.
That's the hard thing in Epic with the progressions: spellcasters don't get new spells, but they already had all the spells they needed earlier on; they only get higher spell slots for metamagic feats and epic spell slots for making ridiculously powerful custom spells. The one benefit of martial characters (BAB) essentially cripples to no iterative attacks and no better BAB progression, and the only saving grace is that all saving throws progress as good, but that's nothing because everyone does the same.
As for the feats, again: they would still be good for pre-epic play. For example: Bulwark of Defense should have existed as a pre-epic option, because Defensive Stance needs a reason to exist, while Rage gets much, much better just by getting levels. Chaotic Rage? That can be reasonably epic: all your weapons are treated as if you had anarchic weapons, so you deal 2d6 points of damage to non-chaotic creatures by throwing a frickin' potato chip at them when you're raging. Which of the two screams epic? Certainly not the former; the latter, on the other hand, would be pretty unfair pre-epic unless it was a class-based ability.
Example of Epic feats: having Oversized Two-Weapon Fighting and Monkey Grip combine to get Titangrip Two Weapon Fighting, in which you can wield two-handed weapons in each hand and treat as if you wielded both weapons with two hands (now imagine that with Power Attack/Leap Attack/Shock Trooper and pounce, and you basically rain death on your opponent). Bane of Enemies/Death of Enemies is another reasonably good Epic feat set: one grants you bane weapons, the other gives a chance of auto-killing your favored enemies. Another awesome epic feat would be a feat that allows you to deal touch attacks with piercing weapons, owing to your perfectly honed accuracy. All of the three really boost the power of martial characters to epic levels, since by the time you get those you don't need magic items to be awesome.
It's...hard to imagine that you can achieve Epic stuff when you try to pull off stuff like the labors of Heracles or the epic "rocks fall, Philistines die" of Samson, or singlehandedly slaying Grendel in Beowulf's epic, and when you see what you can do...is basically add one extra point to your attack roll, when a spell already could do that 15 levels ago.
That's why I say it's difficult for me to tackle Epic, and that I don't know where to start: I want the martial characters to hit like trains, dodge like if they were made of wind, have weapons break on them when they hit them, punch spells back to the spellcaster like nobody's business (thus, Exceptional Deflection does count like an Epic feat, but I mean punching), getting their levels reduced to 0 and simply get with the last ounce of their strength left in them, move to the wizard who just did Split Ray Twinned Intensified Enervation and lodge all the negative levels on them even if they had Death Ward and were undead already so that they perished even if they died, and other really epic stuff. But that goes with the other problem of epic, and that is GP-02 Atomic Bazooka tagging, arms escalation, and basically being better than the gods by the time they reach level 20. So I think it's better to tackle the problem right from the beginning, dealing with the spellcaster situation somewhat before tackling Epic properly.