It seems to me that Aion has a very interesting property; its blokchain will be able to unite the various blokchains among themselves. In the future, this may become necessary. Since it is already created quite a lot off them.
So in essence Aion is working on a universal standard for cross-blockchain compatibility. While AION is a great project, and ultimately I think very necessary in the crypto-world, Aion is not a project that offers a very unique or innovative use case.