Ok, so I had an idea about how Blizzard may be able to create and implement Epic Armor so to speak.
Upon completion of gaining full 100% reknown the user gains an account bound ring of unique features.
Make it so this ring has its own individual aspect codex where instead of sacrificing legendaries for aspects you are now sacrificing uniques for aspects.
This would open up a brand new meta allowing for very unique builds by potentially allowing 2 unique aspects in the same build that may never have otherwise come about.
Additionally, this ring should not be subject to limited tempering and should be allowed an infinite number of rerolls of all 6 types making it truly 1 of a kind for customisation.