A small but authentic hole in the wall in the Camp - Vitaly. Finish carb loading with their gelato and cookies. And you can get reservations, but the parking is not great.
https://www.vitaly.net/
Also Sapori by Balboa Island. They have a pizza shop to the left of their main restaurant spot and I thoroughly love the pizza there.
https://www.saporinb.com/
For breakfast on Balboa Island, locals go to Wilma’s Patio. I second the recommendation for Bluewater Grill. Not a young, hip people-watching place but really good seafood at reasonable prices.