Are you saying this because people seem to forget about our defensive worries when they think of Aguero, or do you believe we'd actually sign better defenders if we weren't going to sign a top striker, but keep Quag/Matri and get... say Gila?
Both, actually. Aguero would be awesome here, but I would not be willing to spend €45M solely on him as it is rumored around, as that would backfire at us sooner rather than later. The problem with this team was never scoring goals, but conceding. And in Serie A, the best teams in the league, always had the best defense; Milan this year conceded 24 goals, Inter conceded 34 in the previous, etc.
So yeah, I'd be willing to leave a forward line up of Quag, Matri, Del Piero and Toni for next season if it would mean we'll get some solid defenders instead.