I think Xavi will be great coach for Barcelona but he needs time to implement his vision and strategy. Team must be patient and not expect instant success. With time and support I am confident that Barcelona will bounce back stronger in the new season.
Actually Xavi is a suitable coach for Barcelona when other coaches need time to adapt to their players. Xavi can do it quickly and in his first season he was able to give Barcelona the La Liga title. But I have to admit that at that time Barcelona was still supported by strong performance even though they had been hit by financial problems and Xavi was able to do well.
But unfortunately, even though Xavi had tried his best for Barca, the Barcelona president seemed to close his eyes and couldn't accept this. At first they wanted to keep Xavi, but just because Xavi wanted to improve Barca's condition by recruiting new players, Barcelona didn't trust Xavi anymore and finally fired him.
So it's useless discussing Xavi because the coach will no longer be at Barcelona next season. I think there will be a club that will make an offer to him sooner or later, he is a great coach if supported by talented players.