Hearthpwn

Brain Masseuse is just a bad idea. You hope to survive, so you should not give your opponent more opportunities to inflict damage. It will almost never inflict damage alongside Aranna, since either Aranna gets killed first, ot the Masseuse is already dead.

Narain seems unnecessary and might end up filling your hand too much. You aim to draw a lot of cards, which makes a card that adds 2 pretty clunky.

Rest in Peace is a cute idea, but probably also unncessary and it can seriously backfire. I think you'd be better off focusing on a massive draw with Glaivetar and see Aranna as a pure combo card. Giving your opponent a free Yogg/Aman'thul/Eonar/whatever gives them both a damage sponge (remember that Aranna targets randomly) and a potential comeback.

Adding more ways to deal with certain boards seems like a better idea. You might run into opponents who actually do something on their first 6 turns.

All that said, I'm not sure you can draw quite enough and fast enough. Your win condition is to overdraw a ton once you hit fatigue, but to actually win games that way, you need to draw very fast and very efficiently and see the combo arrive on turn 9 or 10, not turn 15. Even Reno decks typically have some threats developed before turn 10, and you cannot stall at all. You also have to expect that some of your fatigue damage (10 or 15?) hits minions. You need huge draw to compensate for that.

A nice idea, but I have some doubts that the DH toolkit is actually sufficient in Standard to support it. I don't think it will work out very often, even against control decks, but just for fun, it's still worth trying out.