If they could get more than 30 million then they could take that money and re-invest it to become stronger than previously.
Yup, they could do it, but not to the same extent since for Zlatan they got Eto'o+49 millions.
But I hope they won't be that successful this time and chances are that they won't. For starters they have Gasperini and not Mourinho demanding the players and creating the team and also, as said above, they'll have much less money at their disposal compared to the Zlatan situation.
I really think that the best they could do is a direct replacement for Eto'o in Tevez. That way they'll do minimal damage, if any. In every other scenario they will lose.