My Idea for new Content - Ancient crates!!

[Eski]

my idea:
-there should be a Ancient Crate per campain (Shuyal,tindirin,...)
-those crates should be super rare
-the only way to open them is by collecting keys in elite maps (number of keys should raise with the level of the campain)
-crates includes :Legendary and super rarely mythics and arcanes (pets and items),Platinum and Gold
-also those crates should be non tradable
Note : as i said above ,those crates should be super rare so there is no point in exploit
Let me know what you think about it