I just decided to make this build, After a succeed ranked game.
Im not going to write a book but still something. ^^

As Seals I prefer HP Per/level because you don't need armor in mid lane.
As Marks as usual take Magic Penetration flat.
As Gylphs take Flat Ability Powers.
And Quintences take Flat Ability Power.

As seals: If you don't want to take HP Per/level, you can instead take Flat OP or Flat HP Regen.
As marks: I dont think theres nothing else than Magic Penetration.
And Gylphs: You can pick Per/Level AP, and 100 mana with Flat Manas is good.
Quintences you should think what you prefer yourself.

Utility Tree: Summoner's Insight proves your flash.
Q: And why to take Expanded Mind, instead of, Good Hands ?
A: You need that Mana and you should not die.

Q: Why 3 Meditation and 2 Swiftness Instead of 4 Swiftness and 1 Scout.
A: It's helpful to have little boost of Mana Regen, And that 5% is not much.