I'm not sure you're getting a lot from the white/blue combination. Neither color is really bringing anything critical. I would consider dropping the blue and going only white. You've got disruption spells with both colors (Dispatch, Mana Leak, and Disperse). I think the blue counterspells don't fit in as well because you should be tapping out all of your land every turn to cast Myr and activate abilities. Dispatch is a good removal spell because you can use it anytime, not only when an opponent casts a spell. Another good white addition like this is Dispense Justice. I'd recommend having 6-8 removal spells to help clear the way for your myr. Going one color will make your deck more stable. A few other cards I would consider are Origin Spellbomb (it's cheap, it can replace itself by letting you draw a card if you're playing white), and Myr Reservoir. The Reservoir will help you regain your important creatures, because they are vulnerable to removal spells. Also, if you think opponent removal spells will be a concern, consider Perilous Myr and Darksteel Myr. The Perilous discourage destroying them and the Darksteel are indestructible. I'm not sure you need the Unwinding Clocks. To me they're what they call a "win-more" card. They can untap your creatures on your opponent's turn, but if you have a lot of creatures to untap you're probably in good shape already, and if you're behind on creatures it probably won't make enough of a difference. Beware of cards that are mostly only useful when you're already winning. You probably don't need 4 Myr Turbines. At 5 mana, they're a late game card. The Shrines and Myrsmiths are better creature factories, because they're cheaper and can appear earlier. Those are my biggest observations. In general, try to keep your mana curve balanced to where you aren't always vulnerable early on. Don't let the Dispatch's fool you being only one mana. They're not first turn cards since you need three artifacts to make them useful. Make sure you have enough cheap useful cards that you can survive to get your big hitters out.
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