Xavi is gathering new experience as new seasons keep unfolding. In the last two seasons he could not make any impact in the Europa and Champions League maybe due to lack of experience to compete with the big coaches but he was able to do so much in the Laliga. I believe with his recent Laliga trophy Supercopa de España, Laliga and semi-finalist in the Copa del Rey Xavi should be able to do beyond the group stage in the CL hopefully qualify for semi-final
That is a very good hope that Xavi must achieve next season in order to make the Barcelona team triumph again in a bigger competition such as the Champions League, because the Champions League always has bigger challenges for all teams so Xavi needs to put his all into it. Organize and train every player who is already on the current team. Apart from that, Barcelona fans will also be very happy if Barcelona can return to competing in the Champions League until the semifinals next season.
Barcelona have some experienced players along with some young talent who wouldn't be a bad team to plan for the Champions League but need better planning first. Barcelona is a successful team in La Liga because Barcelona has won more league titles than Real Madrid so far but they are far behind Real Madrid in the Champions League.
Barcelona's performance in the Champions League last season was very poor which is never expected from a team like Barcelona. If their financial problems are resolved, they should be able to re-sign some players right now.