I would not say that Barcelona will be the same as they were a few seasons ago, which was one of the best times for them. The composition of the players is clearly different and it will also make a little difference to the pattern of the game. I prefer if they do their best first and together with consistency.
It's too early to take a conclusion. The new season has not yet started and how can you sure if barcelona was the same like a few seasons ago only from seeing the result of pre-season? Barcelona need to proves it first. Pre season result was not strong enough to be considered as reliable data to know how good the improvements that already made. It must be taken from real match in the season. There are some critics about lewandowski has not yet made a score since he was joining in the club.
This reminds me with some cases when player very productive in the old club but he can't do that in the new club.
Barcelona showed progressive progress in several friendly matches, especially the friendly match between the two great rivals of El Clasico which Barcelona won.
you can see in the friendly match, the tension in the game was hot, this shows that the two teams are playing very seriously to beat each other.
I think Xavi will make some corrections to improve the squad as a whole. although I agree it is too early to conclude the Barcelona squad is in its best phase, we will wait for the real proof once La Liga starts.