As someone who has heard bother the Ananda, Arya and 6XX (along with many other headphones). The Arya is not an objective improvement over the Ananda, its just different (but not that different).
Above this price point you start hitting huge diminishing returns and esoteric tunings. Just stick with Ananda. If you don't like them, sell them and get something else. Owning the Ananda and Arya is like owning two identical cars with slightly different trims.
If you're talking solid-state amps, it's mostly snake oil.