I would look into the First National. They have a bunch of interesting event spaces, the building itself is beautiful, and the restaurants are good. Or just the restaurants themselves. There are a couple.
Red prime, Broadway 10, and the Ranch have areas available for events. Also, Benvunetis in Norman.
Halls pizza has an awesome patio and inside area on their second floor.
I would look into the First National. They have a bunch of interesting event spaces, the building itself is beautiful, and the restaurants are good. Or just the restaurants themselves. There are a couple.