Jeremy Lin has not played worth the mention your not giving him.... I see Shumpert as a 2, by the way, and I think his game would mesh well enough with Sessions.
I think New York's troubles are bad enough now that they may need to make a move. There is no guarantee that Davis or Bibby will come back enough to make a big difference on the team, which needs a big difference. If they cannot win with their shiny new toys, how are they going to fix it? That said, I am not sure if there are any assets there we really want.