I don't know. I just like variety. I also miss my favorite jungler.
With the right build he could do great clear times with unlimited sustain and heal all of your lanes, not to mention great tanks with speed boots and such.
I'm just always sad Whalen they make changes to pidgeon hole champs into an exact role and spot that almost can't be escaped from.
Having options and choices are good for keeping players happy=good the the game.
And yea, his late game mana atm is rediculous, you almost have to build grail no matter what or be 1/2 useless.
Also, not the mat the new passive isn't cool, like the interactivity with all spells, they just took out one of the best and most unique ways to get it in the game, and unique+effective is always a good thing to have.