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-blind duration 3/4/5
-recall 5/4/3 (or so)
My build is pretty much the same as yours, but for a heavy support/ganking/babysit kotl, I've seen some guys get 2 illu, 3 chakra, then max mana leak.
Nuke without stealing creeps from carries, usually best when with a PL or something...
In a game where you might be soloing, your build is fine.