I choose the gold runes because with zilean he needs to get as much mana sustain and cdr as possible to be very useful. Plus the sightstone. that goes the same for the expanded mind mastery. I do agree about the inspiration mastery though, and I'm testing which masteries are better as we speak :)

Masteries like Expanded Mind or Inspiration are inferior to some Masteries of the offense or defense Mastery Tree. 9/0/21 or 0/9/21 are optimal setups.

The first time it told me that my guide had dissapeared so I remade it -.- I am curious why you say that, I would like to understand the reasoning, if there is something different you think I should be doing.

Why double posting a guide?

Gold Quintessences aren't suitable and you spend way to many points in the Utility tree.