White Myr

thanks for the help,
I only have one indomitable archangel, but I like the idea of the whispersilk cloaks and the Heavy Arbalest,
but what should i take out?
Should i completely take out all the red and just make it a White deck?

You're not running enough red and it's only helping control your opponents creature count if anything.

I recommend dropping the red and using some Darksteel Myr. Infect, Wither, and Trample would remain a problem but that's a problem for everyone. A couple more Myr Battlesphere's would be nice too. The infinite combo for the Heavy Arbalest trick works for it's ability as well. You can tap as many Myr as you need when it attacks and the 4/7 Battlesphere gains +X/+0 where X is the number of Myr you tapped. It also deals the X damage to the defending player. Assuming your opponent had 20 life and you tapped 20 Myr when you attacked with the Battlesphere, it wouldn't matter whether it was blocked or not.

If you droped the red, you would drop the 4 Iron Myr and the 8 red spells. You could go down to 20 basic land cards, all being Plains. This would reduce your deck by 14 cards. The Great Furnace's would go with them, dropping your deck by a total of 16 cards. You would have a 59 card deck with what I see up there if you dropped the red.

I was thinking i should replace the iron myrs with Razor Hippogriph's just for the flying and returning artifacts from the grave yard, or should i put in the darksteel myrs.
Can you recommend any white spells (or artifacts) to put into the deck instead of the red spells. ( or should i just make it a 60 card deck?

Here's a list of some good looking non-creature spells. A lot of them look good for your deck but you should really limit it to cards that you would prefer.

Instant
Mighty Leap {1w} +2/+2 Flying (Instant)
Soul Parry {1w} Prevent 2 creatures from dealing damage
Silence {w} Opponent can't cast spells
Brave the Elements {w} Creatures controlled get prot from color of choice
Righteousness {w} Blocking creature gets +7/+7
Safe Passage {2w} Prevent damage this turn

Sorcery
Day of Judgement {2ww} Destroy all Creatures
Iona's Judgement {4w} Exile creature or enchantment
Open the Vaults {4ww} Return artifacts/enchantments from graveyard to the field

Enchantment
Arrest {2w} Can't attack/block/activate abilities
Pacifism {1w} can't attack/block
Tempered steel {1ww} Artifact creatures you control get +2/+2
Armored Ascension {3w} +1/+1 for each plains controlled and flying
Honor of the Pure {1w} White creatures controlled get +1/+1
Leyline of Sanctity {2ww} player gains shroud
Marshal's Anthem {2ww} Creatures controlld get +1/+1 (multikicker graveyard res{1w})
Journey to Nowhere {1w} exile creature
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I like the Safe Passage, Day of Judgement, Open the Vaults, Arrest, Pacifism, Tempered steel, Marshal's Anthem, Journey to Nowhere cards. It's still player's preference on what you should use.
Leyline of Sanctity is also a good side deck card because it stops players from directly burning you but it's not a good card to always main deck. People build decks differently because they think of using cards differently. Good luck on completing this. (I only went back to M10 since I didn't know what kind of cards you wanted to use.)