Do you need a reservation for 2 people on a Sunday evening?

Early dinner, around 4:00-5:00 you probably can get a table, but later, definitely want to make a reservation

I would make a reservation because if you don't you will have to wait.

Yes, especially around 6:00 !!

Yes

You can call ahead for seating, except for the bar area, and there are many tables availavble in the bar area.

You might have to wait. You can almost always sit at the bar and eat

Absolutely make a reservation