In this match Xavi also did the same thing by playing Cancelo in a position that was not his best position 
Actually if I look at the current composition of the players, i prefer to enter Kounde as a right fullback and restore Cancelo's position at left fullback to replace Balde.
Balde is a pretty good player but he is a slow player so this could be a problem when the fullback is too far in the opposition defence he won't be able to get back to his position properly when the counter attack is launched.
At the moment the first half between Barcelona and Almeria is over and the score at the end of the first half is 1-1. Of course this must be a concern because if in this match Barcelona still fail to win full points then their position in terms of points could be even further away from Madrid and Girona.
Xavi has always provided a situation where players must be asked to be ready in several positions even though it's good if players can improve but sometimes not all can be like that. Actually if I look at the current composition of the players, i prefer to enter Kounde as a right fullback and restore Cancelo's position at left fullback to replace Balde.
Balde is a pretty good player but he is a slow player so this could be a problem when the fullback is too far in the opposition defence he won't be able to get back to his position properly when the counter attack is launched.
At the moment the first half between Barcelona and Almeria is over and the score at the end of the first half is 1-1. Of course this must be a concern because if in this match Barcelona still fail to win full points then their position in terms of points could be even further away from Madrid and Girona.
Talking about Balde and Cancelo I would agree with what you said if we talk about the speed issue because seeing from what is happening right now Balde still cannot be compared to Cancelo but on the other hand another possibility of Xavi trusting Balde more is to give him flight hours because we know that even though Cancelo is very good in the game and speed but he will only last 1 season which of course if there is no habit and time for Balde from now on maybe it will be complicated for Barcelona in the future.
In yesterday's match Barcelona seemed to be still very troubled to maintain their performance, especially for defense problems. They struggled to face Almeria and almost even played a draw in this match if Sergio Roberto did not become a hero with his Brace in this match.
At the beginning of the season he liked to explore some players like De Jong or Gavi who were placed in positions that were not really their positions and indeed it can still be said to be successful even though I still think it is not optimal and now he is trying again in defence even though if you look at this match their defence is quite problematic especially with 2 mistakes made by their 2 defender centres.
It's a good thing they managed to get the 3 points in this one because otherwise I think the wave of criticism would have continued for Xavi.
Today we will see Madrid take on Alaves. I'm quite looking forward to this one as it will also be quite important for Madrid to reclaim the top spot which is still held by Girona due to their impressive form.