Glistener has no place here, he doesn't jive with the plan of doing 20.
Maybe Imperious Perfect instead of overrun if that would speed up your clock. You can even land him on turn 2. I personally think that another elf lord besides the potential one in the Noble would boost your clock, as you could just romp their face in. Then if that just isn't enough if you're playing the one Noble elf lord which turns all your guys into mana dorks you can drop huge green beats.
Or you could just play Elfball, if it's viable at all, I dunno as I kind of hate that decklist.