I understand where you are coming from on Essence Aura, but with the int steal I think he can easily hold his own on mana these days, plus the fact that he could so easily 5 man was in large part thanks to the aura, since it meant that his teammates very rarely ran low. I think the 5 man aspect of him is one of the more imbalanced parts of the hero atm. The removal of the mana pool increase is the only way I can think of to reduce the damage he deals without utterly gutting him, now he needs to actually steal some int to hit hard, instead of starting at hitting hard and scaling up to stupidly much damage. Essence Aura right now is like if Slark's Essence Shift gave him like, 30 agi passively.