Ah, yes. Suspension of disbelief is fine when you can handwave it and attribute it to spellcasting, but not when it comes to the nonmagical classes. I will never, ever get this. Look, people. Epic-level spellcasters can do things that make practically ANY superhero (with the exception of the Doctor, who IS an epic-level spellcaster) look rather pathetic. Dragons can fly, giants can walk, unarmed dudes can punch holes in iron golems. It's FANTASY, people. Confining the skill monkeys and fighters to some definition of "realism" while you allow the monsters and spellcasters to run rampant over same is not only unbalanced, but unfair.
Nor, I would argue, is Aragorn, or even Conan, an epic-level character of the power required to pull these stunts off. Nor, for that matter, are the kinds of fantasy in REH's stories or LotR on a level with D&D. If you want to talk about a character in, say, the Lord of the Rings actually being able to pull off those epic skill uses, try Sauron (Bluff) or Saruman (Diplomacy). These are quasi-magical abilities, people, and they are meant to be used in a universe in which REAL magical abilities (ie spells, supernatural abilities, or SLAs) are far, far more powerful. None of these epic skill "uses" is actually particularly USEFUL by the time that PCs get access to them. Almost none of them can be accomplished by anyone below 50th level without serious magical aid, which makes them effectively just like spells anyway.
Finally, it's not like myth and legend *doesn't* set a precedent for many of these. Aesclepius's healing skill was able to bring people back from the dead. The wuxia masters could run up trees and jump from cloud to cloud. Numerous gods and heroes, from Krishna to Hermes to Bugs Bunny, have been able to talk people into doing or thinking practically anything (Bugs could talk Elmer into taking a dip in a pool of acid with no sweat). And Luthien sang MORGOTH (probably a god by D&D standards) a lullaby powerful enough to send him to sleep. None of these are explicitly represented as "spells," and nor do the legends draw a line between the possible and impossible in terms of feats of skill. That's what makes them legends.
You don't like this sort of thing? Fine. But then you should probably not be allowing your spellcasters to obliterate every opponent on the field of battle in six seconds without showing strain, corruption, alteration of the fabric of the universe, or any of the other side effects that stories attribute to magic. I don't recall Theleb K'aarna being able to turn invisible, fly, and destroy an entire army with simple effortless waves of his hands. I don't remember Thoth-Amon being able to spontaneously generate his own demiplane. Does Rackhir the Red Archer have the ability to fire fifty arrows at targets as far away as the horizon within 6 seconds?