I wouldn't mind playing Nunez upfront as a second striker supporting McCormack. In a Trequartista role as the Italians say. Once Becchio comes back put him behind the strikers with Howson. Although what i'm wondering unless we play a lone striker, we are going to have only room for 2 central midfielders (2 strikers, 2 wingers, 4 defenders, 1 gk, 2 central mids=11) but we have three CMs Nunez, Howson, Brown, would you play all three and use a lone striker, or play 2 (which two?) and an extra striker?
loan striker when becchio is fit for away games, we need to be able to mix it up a bit and go 442 though.
With McCormack or Nunez playing with Becchio upfront, they could always drop back into a midfield role if we needed it. I'd play 5 in midfield, especially seeing as Becchio and Somma are out. Have Brown in defensive midfield alongside Clayton or Howson, and then Nunez/Howson behind a striker.