DedWards

I personally prefer Pyrohemia over Pestilance when wanting to use Stuffy because the red opens you up to all those pretty global burn spells :D

Selesnya Charm is still a good mainboard option. It can produce a creature at instant speed, exile an annoying fatty or just count as a pump spell that grants trample. All of which sound good for this deck :p

Bronzebeak Moa is quite a cool card, it won me a game in the prerelease :)
Kinda sucks that it can be chump blocked though :( So, I suggest more tample in the form of Rancor and / or Selesnya Charm in addition to Unflinching courage. And for more combat tricks, Cloudshift or Restoration Angel mite be a good fit.
Growing Ranks and Parallel Lives feel a little slow to me. They need time to be set up and then more time to actually do anything. Just last week I managed to beat an opponent relying on them because I killed all the tokens before Growing Ranks could do it's thing. Parallel Lives is still a pain though.

A friend plays a simila deck. He likes to put his ciphers on an animated Dimir Keyrune :)
This helps it survive mass kill like Supreme Verdict :p

Blacer's do work. Mana abilities are abilities that add mana

As you still cast the creature, even though it's for free, it'll count towards Storm effects.
Another use, that I'm working on in a deck, is to use Falkenherth Noble with the looping of Myr Retrievers :P

Mana abilities are abilities that grant mana not abilities that cost mana.

Mry Retriever. Look it up and tell me what you think of it's interaction with Heartless Summoning

Like Wight of Precinct Six and Jace's Phantasm

I kinda agree that the bracers seem a little useless with only 1 creature to get the bonus off of.

Cards like Ætherize and Killing Wave are nice for hordes of creatures. Ultimate Price, Unsummon and the like make good spot removal.

Then there's creatures like Wight of Precinct Six that can make the opponent consider how they attack (Wight should be big).

My bad. It's already banned. Secon Sunrise's banning starts today.
I'm quite sad that Seething Song is banned :'( Means I have to get creative with storm...

Just for fun, eh? I find a set of Kokusho, the Evening Star is more fun to Dragonstorm for than the Hellkites :p

Have you thought of working in some Ready // Willing?

Sadly, as of this friday, Seething Song is banned in Modern :(

There's two blue creatures you may want to consider using:
Grand Architect
Etherium Sculptor

I'm not sure mill is a good idea for EDH. You have ± 92 cards to mill through where a "normal" deck only has 53. That's double a normal mill and I have yet to see a mill deck outpace other deck types on a regular basis.

That said, I think you're brave to try mill in EDH.

PS
Who's your General?

Nice deck. Knights have always been a strong tribe, but why no Kinsbaile Cavalier ?

An interesting option you could add (though off colour) is Essence Harvest. With Harvest, you don't even have to attack to win :)
Another option that also requires black is Vizkopa Guildmage. Activate the Guildmage's second ability, then play your combo :p

Best detain combo I've heard of and hope to see but not play against:
Lavinia of the Tenth + Conjurer's Closet

Just in case I wasn't clear enough, here's an example of what'd happen:
Let us say you're on 12 life when Avatar enters the battlefield. Avatar will enter as a 12/12 and trigger Trostani. Trostani will try give you 12 life as the Avatar (that is now on the battlefield) has 12 toughness. The life gain triggers Rhox and he'll double that 12 to 24 (effectivly granting an additional 12). Once all this is done, you gain 24 life (putting you on 36) and the Avatar will be a 36/36. No additional life will be gained from this combo and the Avatar will not become bigger.