Draw Burn

Niv-Mizzet isn't that crucial to your deck, so consider not running 4 of him. Or her. That dragon. Anyway, it's indeed an engine within itself, but it's far too heavy and you don't really have acceleration for creatures in your deck.

I see your deck is based on drawing while burning, but I don't see that much drawing in your deck. Not at once and not steadily. For instance, I suppose you could increase the number of instants and sorceries and give up a little bit on the number of creatures. You've got 20 creatures and 18 instants/sorceries. I understand the need to protect your deck against potential threats, and in your case that'd be cards with lots of fast creatures you can't seem to stop, but it's more important to develop your core for now.

I have two suggestions for you:

*See what's really important for your deck right now. If it's the act of constantly replacing your burn cards with other burn cards that also have the power to replace themselves, consider that drawing isn't the only way to do that. Magma Jet, for example, is a great way to burn and filter your deck. This way you can remove the excessive amount of cards that eliminate maximum hand size. Graceful Adept is particularly bothersome right now, and you don't need to worry about discarding anyway if you're not drawing that much. And even if you are, they can still be useful there with cards such as Pyromancer's Ascension, Past in Flames, Recoup or Snapcaster Mage.

*Go knee-deep in your own experiment before sorting out what kind of control you need. Use more reckless cards like Epic Experiment and Increasing Vengeance while taking away Hypersonic Dragon and Smoke. Then you'll have to put more actual burn cards so as not to depend too much on Guttersnipe.