Ba is rather effective in the hole imo - that is, playing from deep. The Cissé-Ba partnership hasn't really clicked as such but it will happen for them imho. Their games may be similar but Ba is different in that he can play in a somewhat non-advanced forward role. Cissé and Ba just have to learn about each other's game and interchange roles when need be.
I reckon a formation along the lines of a 4-4-1-1 could work (with Ben Arfa having a free role from the left/right wing). But, in any case, the formation Pardew lines up with will be very dependent on the opposition. If it's a lower mid-table team, then I think we might see the return of the 4-3-3.