What would make the optimal reward scale, from Clearers to the plain-ol' Daily player

[Brannigan]

I think raid weapon should've been i215 though.

I really like the current weapon setup (dip available from last boss and a weapon drop as well, so 2 weapons per week), but it only works as long as you can't get dip outside of A4S. Relic would have to be like 205 also or require something difficult to finish it (lol, not gonna happen)

Well...in my days, the difference in reward was: -

No really. You got the exact same things regardless of whether you chose Very Easy or Infernal as difficulty. Or whether you set the difficulty bar to 1 or 100 in games with a slider. Later on (especially on Steam), you got a different achievement for clearing each difficulty, if at all. And that was it.

It's a concept that, for some odd reason, works for millions of single-player games. Modern titles as well. Yet in MMOs, it seems to be unfathomable.

This is an odd comparison. Alexander Savage is not a more difficult version of The Diadem, it's completely different content that happens to be extremely more difficult but rewards worse gear for some reason. Defeating Bahamut in FF8 gives better rewards than defeating Ifrit because one is much harder than the other. Going out and murdering some random wolf or bandit in an open world game doesn't usually give better rewards than killing a dragon.