Problem was the lax attitude, not personnel. Alaves, while solid under Abelardo (as with Pelegrino), played extra time midweek in Copa and with Barca pressing more we would have cracked them open and had we not been complacent and soft (4 fouls entire match), I doubt Alaves would have had those chances.
Besides, Suarez, for example, had a poor overall match and who's to say Paco wouldn't have buried some of those chances.
I also maintain that Iniesta and Coutinho shouldn't have played together.