The first is just having a high baseline, it doesn't let them go above and beyond. It's pretty much super-advantage. The second lets them break mundane bounds - but only by about 20%. For me the Heroic tier is anything I'd see in Hollywood action movies or non-supernatural martial arts movies rather than real life. Indiana Jones and John McClane aren't superheroes for example. Nor is the average Jackie Chan character even if no one could actually take the punishment Jackie's characters do.
I agree those examples are heroic (what I want), not superheroic (what you want).
Indomitable Might and Primal Champion are not to me remotely outside the bounds I'd see in an action movie for a character whose schtick is strength.
Maximum human STR is 20, Primal Champion allows you to be better than human, i.e. "super-human" which makes it "super heroic" IMO anyway. But as I said, what is super heroic to you is probably crazy super heroic to me. For instance, there are lots of super heroes whose shtick is strength, but many of them are stronger than others--- still, their all super heroes.
Utterly irrelevant in play especially in a world with elves. A human with timeless body will remain in their prime for less time than an elf without it.
I was more focused on the not needing food or water---which is definitely beyond human.
Improved unarmoured movement letting them run on water on the other hand to me does push them over the line.
Sure, but as I wrote I was focused on the non-magical. Now, if you want to think in terms of Chiun running on water, you just have to run "very fast".

Still, well beyond mundane, so super heroic.
Seriously? I'd have accepted Lay On Hands. But Divine Health isn't to me remotely in the realms of superheroism.
You are
immune to all disease! How is that not a super hero power!?!
But seriously, rangers have spells.
Right, which is why it is hard to argue them as "martials", since the are half/half.
Again Reliable talent is super-advantage. I'd consider e.g. most of the Leverage crew to have it. It's in the Heroic "Hollywood action movie but no actual superpowers" rather than the superheroic tier.
Which is why I also added Stroke of Luck.
A wizard's origin is normally "Somebody taught them" and sometimes "They went to the library".
For some wizards, sure, but the examples were characters such as Gandalf and Merlin as well, which were non-human in origin.
And if the wizard's origin is "semi demi hemi god" then that should be open to fighters as well.
Certain non-human races, such as Goliaths, with features like
powerful build, can easily place them well beyond human capabilities. Again, i.e. super human and thus the things they can do is super heroic.
So why are wizards allowed to be demigods but fighters aren't when there are a lot of fictional and mythological fighters who are demigods?
See above as to some of those examples.
And wizards aren't "allowed to be demigods", their spells give them incredible, but very limited in use, power. Martials excel elsewhere. Do I think it is on an even keel? Certainly not and I've said so repeated. Even so, spells are not the be-all end-all in the game. I've seen plenty of wizards and other casters falter when martials strive. As always, (obviously) YMMV.
And as far as I understand it, elements of Mythic Odyssey of Theros gave you the chance to be a demigod basically? I don't know as I don't own it.
Finally, as we've covered (repeatedly), what makes a PC super heroic is a matter of opinion. I think the class features I've outlined above do many PCs super heroes. They have abilities mundane people will never have and/or can do things they can not do. Many (at mid levels) are more heroic in nature, other features (especially at higher levels) are super heroic IMO.
Again, might not be the super hero-like power you want, but its there either way as I see it.