The ShiftstonedEternal Power Calculator is a deck-building tool that visualizes your odds of drawing enough Influence and Power based specifically on the cards found in your deck.
I too haven't crafted the other 2x Ayan, the Abductor that I need so I replace 2x with Dark Return. Although functionally somewhat different, there are a LOT of cards worth Dark Returning in these lists. Works well at mid-rank Masters.
Ayan is really good, but not necessary for the success of Xenan Control.
I've tried many things as a "replacement" looking for cost vs. versatility: Memory Dredger, Suffocate, Xenan Augury, Bloodcall Invoker, Scorpion Wasp, Sanctuary Priest.
The one I ended up choosing most of the time is Blistersting Wasp. At a cost of 2 for a 1/3 it is a good blocker, flyer, and deadly.
Ayan is really good, but not necessary for the success of Xenan Control.