1)
Where should Hashem return us?
1.
Rashi: From Galus Bavel; Mordechai was there.
2.
Radak: Return us to You, i.e. prepare our hearts to You.
3.
Malbim: They should return to their land, and the enemies should not defeat them.
2)
Why does it say "v'Ha'er Panecha"?
1.
Radak: At a time of anger, He hides His face. At a time of desire, He makes His face radiate and oversees for good.