There's no ban, education or help that will change him.
Clearly it was not a conscious decision to bite, I don't believe he planned to dine Italian. However in the heat of the moment, when things are not going his way, he snaps and bites.
And watching the many gifs, it is true that the shoulder hit him first. And at that moment, his brain snapped and he bit. No amount of "education" and "help" will solve this, it's instinctive. Given the right conditions, he'll lose cognitive control and bite again. To me, it's definitely an illness rather than just cheating.
That said, FIFA should throw the books at him. An inability to control himself is not an excuse or defence. Given this is the third bite, I would say 1 year global ban with a suspended life time ban.
And unluckily for Suarez, the WC, with the global audience, is not the time for FIFA to show leniency. They would not want to look weak. I fully expect Suarez to be hit very very hard, perhaps harder than what his crime justifies (even factoring that's his third)