i know many will disagree with that, but i feel that in the attacking phase we are probably the WORST teams of those who are fighting for a Champions League spot, bar lazio maybe.
roma, juventus and napoli can rely on many strikers, while half of our goals come from icardi. we cannot just pray that he never catches a cold. besides, he will have his fair share of bad days, like against torino.
candreva is not a scorer, perisic works his ass on the flank which prevents him from scoring much.
we need someone who adds goals and pastore can certainly score 5/6 goals in half a league. so by all means, let's go for him. he might not be the kind of player that fits the system best but i'm positive he would be an added value.
to those who might argue that roma has scored less than us: true, but i feel they don't depend on one striker and sooner or later they will add schick: their top scorer is dzeko, 7 goals out of 23, while icardi scored 13 out of 25 goals.
edit: right, 13. the point stands.