After getting bad results from several previous barcelona matches, of course with this victory it can make Koeman and his squad smile a little, I saw in that match ansu fati began to have a very important role in helping barcelona comeback but it seems he doesn't look really optimal 100%.
Talk about the finances of barcelona, I think barcelona will take a long time to fix these problems, especially now that they have a very large debt to the other club
Now it is very important to return a positive spirit to the team, as it was before. Perhaps this match with Valencia will be able to become a watershed match that will allow Barcelona to start winning. The start turned out to be bad, but nothing critical happened and Barcelona is only 5 points behind the first place (until Real and Atlético played their matches). I think that this difference can be won back throughout the season if they start winning.
Yes, right now barcelona just need consistency in their game to be able to catch up on points from their eternal rivals (real madrid), in my opinion koeman should be able to take advantage of the remaining matches to be able to get as many points as possible before mid-season or until the January transfer market later opened, so that they will not have too big a difference in points with other teams, moreover maybe other clubs will strengthen their team with new players and of course it will make it difficult for Barcelona to beat them later in the second leg match this season, because to be honest I a little doubt if Barcelona will have a lot of money to be able to improve their squad in the January transfer market later.