I think Barcelona still should make two transfers to specific areas. These areas are defensive midfield and centre-forward. Because in the defensive midfield there is still only Oriol Romeu. Of course players like de Jong and Kessie can also play there. However their main positions are central midfield so it is better to use them there.

For the other position there is only Lewandowski there. Barcelona don't need to spend so much money for bringing a striker. They can even loan someone who can be useful in Lewandowski's absence. Signing a backup striker should be even the priority for them.