Smetto Quando Voglio-Ad Honorem provides examples of:!!
The Bus Came Back: Er Murena was almost absent (he appeared in one, brief scene, with his voice altered and never showing the face) from the second movie, but featured in the trailer for the third. Pietro's professor will also come back (although how big his role will be is unclear).
Grand Finale: Set up to be one for the whole trilogy.
