Adaptive Armour.
This is a feature i came across in SWTOR, and i have to say - i am a big fan of it.
Its the ability to wear any item you want, and then customise it with enhancements so its statistics are as effective as any other piece of armour would be at your level.
So you can level your favourite "look" with you indefinitely. If you have the right enhancements for it of course. Its a roleplayers dream, and its almost a guarantee for even more unique looking characters. So you avoid the "all high-end players look the same, and nobody feels special anymore" issue.
In my opinion, i wouldn't mind Elder Scrolls Online developers create their own take on this. In fact, i would welcome it!
So the question is: Would you like a similar feature in the Elder Scrolls Online?