Can't say to be honest. It is going to depend on how long he is able to remain at the top of his game and with full health and fitness. Neither of which I am terribly convinced of at the moment.
If he can live to see the end of the Federer dominance, he may sneak in one or two. But I dont see him winning more than that somehow.
And I agree - step one is regaining his ranking, and returning to full fitness.