It wasn't such a bad idea to try to build a fresh team to play with good teamwork without relying on Messi to carry the team. Indeed Barcelona's biggest flop this season was getting eliminated from the champions league, good thing they have another chance in the Europa League to rewrite the wrongs this season. If they can win the Europa League it could erase their failure in the champions league from the minds of the public.
I don't expect Barcelona to fail again this season in the Europa League even though its journey to qualifying for the last 16 is never easy. Beating Manchester United was a tough task, I never thought it would be easy but this season Barcelona and their players seem more experienced than ever.
Even I don't think Barcelona's failure in the Champions League this season hurts too much, that's because I recognize the superiority of Bayern Munich and Inter in the group stages. But after that failure, I think Barcelona are looking stronger now and they have to do something in the Europa League. I believe in their ability and their players, so there is hope to win and qualify even if it means against Manchester United.
To you, Barcelona's Elimination from the champion league doesn't hurt much. But others may not feel the same. Even if Barcelona should win the Europa League, it wouldn't be enough consolation for elimination from the champion league. moreover, their proximity to the Europa League is not ascertained especially now that Manchester United is gradually revitalizing their form, and don't forget that Sevilla, Roma, sporting Ajax, Juventus, and Arsenal are also stronger contenders in this Europa league race.