He inherited a Barca team that was in the process of tearing itself apart with the likes of Deco, Ronaldinho, Etoo doing whatever they wanted.
Pep brought git rid of them and brought through the likes of Pedro, Busquets and established Messi as the focal point of the team
Could be interesting if Barca appoint Koeman. That team needs a strong leader and a CB and if im not mistaken, Koeman has a very good relationship with a certain 'werld klass centre back'.
La liga has dominated Europe for the past 6 years, 9 of the past 12 winners have been Spanish clubs. Not entirely certain that can be classed as a decline