Pastorello suggestion or not, Keita could be a concrete option in case we offload Pinamonti. I doubt we will go for Satriano or Salcedo as a 4th forward. In that case, better keep Pinamonti!
If Pinamonti is gone, we're going to need a new forward and i don't see many better options than Keita. Who could we realistically get?
Dzeko has a high salary so he's out of question even if Roma terminate his contract. Now that Conte is gone, Diego Costa could be an option but he had serious fitness issues at Atletico last season. There's Simy from Crotone who could be available at a low cost but i think he was more suited to Conte than Inzaghi. Personally i would go for Jovic from Real on loan. I think he could do well under Inzaghi though he's coming from two poor seasons at Real so he would be a risk. And then there's Keita who has already worked with Inzaghi, has already played for the club and you know, more or less, what to expect from him. I don't see any better options available.