I would love to see something like this where you could use these awesome new Mats to improve older legendaries.
For example, you could do something like this: (don't rage at the numbers, just an example lol)
Odyn Son + 5 Demonic Essences + 5m Gold = Level 60 (ilvl 63) Odyn Son
If you do it right you could use it as another much needed Gold sink
Some of the lower level legendaries have really cool visuals and/or effects and/or set bonuses that would really diversify high level bulds if allowed to scale up to ilvl 63.