It wouldn't be all that much of a stretch (certainly not for
PJ and friends) to have Galadriel at the White Council and at
the siege of Dol Guldur. More screen time for Gandalf, a
big battle scene, and not such a long gap of Gandalf in the
two hobbit movies. (Splice in seperately the White Council and
Dol Guldur, perhaps when Bilbo battles the giant spiders and
when he helps the dwarves escape from Legolas's daddy).
Now what elf might be in that drinking scene with the butler?
