Rafa returning to tennis is great for the sport. Unfortunately during his absence, Andy Murray has risen to new heights and is now going to be a deadly foe alongside Djokovic, standing in Rafa's way. Basically Rafa is going to have to go through BOTH these guys to win anything. Not sure I can see anymore AOs or USOs for Nadal with these young hardcourt monsters standing in his way. Wimbledon is going to be risky for him. Basically RG is his only remaining crown that he's a favourite to win.
He's not going to win anymore non-clay Masters titles. I see the Fedal era is nearing the end in terms of domination. I also see Del Potro being the 3rd man alongside Murray and Djokovic who is going to be a roadblock for both Nadal and Federer.