It's quite obvious that Barcelona is not going to win the La Liga title. But they still made quite good improvements. So, I think right now they will concentrate on being in the top 3 in the La Liga table and they will be really motivated to win the Europa League title as it's already a step down for them.
Yes, it may be too hard to win La Liga. at least, Barcelona can survive in 3-4 standing if they can play consistently.
However, they have proven that they have made many good changes, moreover on their player performance. Xavi and signal and manage their team players very well, better than previously. Currently, Barcelona has played greatly to defeat more opponents in several matches.
For this UEFA Europa League, maybe Barcelona has the chance, although there is also Sevilla. For the next match, they will be against Galatasaray, yeah Barcelona may be expected to get a higher score for a higher aggregate. If they can play consistently like some previous matches, they can exactly win it.