I think the team that Xabi has only needs some slight changes, not a total overhaul of all lines. They have good players on the team. However, their performance may have changed with the implementation of the training patterns and game strategies applied by Xabi. They need to adapt and quickly adjust for team cooperation. Managing good players is certainly not easy.
I expected Barcelona to focus on strengthening their defense this season. But Barcelona did not buy any defenders. Barcelona only bought goalkeeper Garcia. I think barcelona needed another experienced defender in their squad.
Since Barcelona performed well last season, so that Hansi flick did not try to make any changes to his squad. As well, we know that Barcelona management is in financial crisis. Perhaps this is one of the reasons why Flick did not put any pressure on Barcelona management to spend money. We still do not know whether Barcelona players will be in the same great rhythm as last season next season. However, since the bonding between the players is very strong, good results can be expected from Barcelona.
Last season, Barcelona's defense was really disastrous which was the reason they couldn't reach the Champions League finals because the porosity of the defense made them concede lots of goals even though the attackers were very creative in scoring but their defense made many mistakes. If not for the financial constraints the club is facing they could have signed quality defenders who can take charge of the defense area so that the goalkeeper won't experience so much threat and pressure from their opponents. The team can still manage the defenders they have since their strikers are very active in goal scoring, even when they concede they can still put things in order. Since they won the La Liga last season, they will still start the new season with good feelings and high morale.