Gio is a beast, but will never be on Messi's level. And believe me, I wish it were true but no way.
Outcast, I like how you put it. Without players like Messi, Kaka, the machine won't function right. You look at C.Ronaldo, he's a special player but the machine doesn't depend on him. He's very much replaceable IMO and his "tricks" are more for show than in the spirit of trying to WIN the game.
And Ronaldinho now is nothing, in his prime he was the best. But I still see Kaka and Messi as better players now than he ever was. Not as skilled with the ball at their feet maybe, but overall way better players. Ronaldinho needed the ball at his feet to do something, Kaka and Messi change the game without the ball as much as with it. That's how you can tell who's on the next level and who isn't. R9 and Zidane were def on that level...