If we're only talking club level then I think Messi's hundreds of goals far outweigh 1 extra league title.
Messi just turned 27 though, Xavi is 34 and rumoured to be leaving the big leagues.
How about the four times world player of the year trophies?
All true facts, I only replied to the question of naming a player who had won more, at no point did I say Xavi was better than Messi or discounted whayt he had achieved. I could easily have picked Iniesta or Victor Valdez who have both won World Cup/s in addition to matching Messi's tally of trophies.