So, I actually don't think it is going to be much of a competition between them and Real Madrid. I hope that it will not be as one-sided as it was the last season. That I am not going to be surprised if it is. It doesn't look like Barcelona is going to be able to get Robert Lewandowski.
I agree with you. Only Real Madrid fought for the title last season. Sevilla, Atletico Madrid and Barcelona were far behind than Real Madrid. But next season will not be like that. Barcelona is increasing their strength. Although Barcelona is not financially stable now, they are spending enough money to strengthen the team.
In last season, Real Madrid were on good run and with this luck was also giving them good favor because Barcelona having the worst start of season and Sevilla and Atlético Madrid were not able to give them good competition, so they enjoy good wins in La Liga and Champions League but in this season as Barcelona is preparing they have to manage things in strong way because now it's not easy to do like they already achieve in last season. But, with the best combination of old and new players they are still very strong and capable of win any title which they won last season.
As many already posted there is no doubt Modric, Benzema, Vasquez are their key players for next season as well and if anyone slumps it's going to be worst for them like Barcelona.