if you are pressed for slots, sell extra charge if you are forced to upgrade, first upgrade to improved burst, then improved reach, then superior duration, then superior cooldown buy in order.
if you have a chance, rushing magic carpet with an open slot is a very valid option at this point in the game you will be playing around your ball and almost never your melee, so sell melee lifesteal for spirit lifesteal and sell spirit strike for one of these items if u dont have slots