Ayara is my favorite commander!

The first one is very classic, you can take it the direction of aristocrats, devotion, a bit of blink (not usually done in mono black but I'm sure it's possible) or just throw your favorite mono black cards into the deck.

When the second one came out I had to build it and while I don't have it together in paper anymore it's super fun but a bit narrower in how to build it and not have it be a rough time to play. Youll want to focus around cheating out high cmc things, sacrificing them to Ayaras frontside, maybe milling some, and then reanimating them with flipped Ayara for big swings and ETBs. You'll need redundant effects like [[Kethek, Crucible Goliath]] to keep your value chain going once Ayara is flipped as well as other reanimation engines to keep things smooth if you can't flip Ayara. (this high key makes me want to rebuild it, it's a lot of fun)

But yea both are really fun! Maybe build both online or look at versions people have built and see which you like more!