Caster's also far overpowered. I mean, counter spell for one blue? You get that out and you'd pretty much have the ultimate counter deck, period. Now, maybe if you made it that she has to tap to use that ability, but even then...
Plus, on white Saber, you need to reword the text for magic resistance to be just like black Saber's, otherwise... Well, think about it, no spells affect her, and everything other than a land or artifact is a spell, she'd be near invincible. Plus, all that for just 5 mana?
Heck, all the mana costs for those can use some inflating.