I feel like Messi is entering the 2nd phase of his career. The first phase I would consider to be 2007-2013. In this phase, he was all about his insane goal-scoring and the ability to dribble through scores of players. Now it seems like he is changing his playing style just a tad bit. He is looking to be more of a provider and more about efficiency. Remember those insane amount of times he would just refuse to pass the ball to Pedro or Villa (and for a good reason) ?
Now, he has new-found motivation. I expect 2014- until he reaches 32 or so to be another set of magic years. With Suarez and Neymar he knows he has proven goalscorers. I can see him refining his assist abilities even further, with him playing more like an AM just behind Suarez and Neymar. I think he won't score as many goals, but I definitely see him setting insane assist records with Suarez and Neymar in front of him. I think overall, this would certainly set him apart as a GOAT player in many people's eyes (for those who still think Maradona/Pele are better than him).