Interesting idea..there are a few things that I don't like about it though, namely 4 ezuri's (because its legendary, i could see 3 being good though) and you only have 2 nissa's chosen, and only 2 llanowars. it seems like you need a few more early mana-producers, like treespeakers or arbor elves. I like the Prized Unicorn idea though, I might try that actually.
Permalink
Well if you are trying to make argentum armor a more viable option, i think you should add 4 ornithopters and 4 quest for the holy relics, and 4 glint hawks (you probably see where this is going) - take out the certarches, the riddlesmiths (discarding a card is too expensive), the gold myrs, and the silver myrs, take out two steel overseers, replace them with 2 contagion clasps (proliferate is too important in your strategy), and if you can afford the expense add a planeswalker, specifically two Venser the Sojourners would be great, just replace two of the etched champions or something with him, it would be fantastic.
I would take out one of the Ezuri, Renegade Leader cards (its legendary after all, 2 is plenty IMO) and one of the copperhorn scouts, and replace those with 2 Vines of Vastwood cards, those are great to stop spot removal or boost a guy up +4/+4 which is always nice. You could also consider adding in Predatory Urge to get rid of fliers or annoying blockers. In my elf deck I run 4 Treespeakers instead of 4 Arbor Elves but maye that isn't too big of a difference. Like someone else said, strength of the tajuru would also be useful to help with your second win condition as well as probably a 4th chosen and a 4th warcaller. Also, maybe Asceticism should be side boarded for if you play against red/black decks? After all if a deck is only playing those two colors there is nothing they can do about enchantments, so its perfect against their removal.