I'm not so sure a Plan B type of striker is enough to be honest. That still does nothing to fix our Plan A, which is very lacking in scoring. Messi is the only one you can depend upon to score consistently. The team would benefit more from an all around striker to be your everyday starter, IMHO.
BTW, getting a striker does not mean Messi moves to then wing. Argentina plays with not one, but two strikers alongside Messi and he still plays centrally, and leads them in scoring.
Bur Argentina plays with 2 CM and then 4 attacking players with messi in a free role. Barça style is a bit far away from that, don´t you agree?
Where would cesc and iniesta play?
Messi can play in the wing and still score a lot of goals. The team should come 1st.