Just a minor point: this isn't a mill deck, it's a discard deck. Milling is when you get rid of all the cards in someone's library, not in their hand. I was just confused how you were going to mill in
in standard given the only mill cards are
(eg. Archive Trap, Tome Scour, Hedron Crab)!
I reckon you can do better than Mind Rot (Hippies and Nyxathids and Megrim are all just much better turn 3 plays) or Keterekt Parasite (you've only really got Slavering Nulls as a
permanent to go off - if you're serious about the Parasite, then you should be playing 4x Veinfire Borderposts in your lands (count them as half a land most of the time)). I think you'd be better off playing more removal in the main deck; you have loads of ways to trash their hand, but no way to deal with something once it's on the table. I would definitely go with Bolt for that, maybe Doom Blade.
What about Bloodchief Ascension instead of Megrim? You get it out on turn 1, you hit them 3 Nulls, Hippies or Specters and then it keeps you alive at the same time, and triggers when they cast spells. Something to think about.
Thranduil