When I ride Marina del Rey to Redondo and back, I stop at either Cheesecake Factory down there (I know) or Ruby's Diner b/c they're easy and have good bike lock-ups.
Back on the Beach Cafe
On the Waterfront Cafe
Cora's Coffee Shop ( a couple of blocks east of the bike path)
My favorite breakfast/lunch place in the area is Martha's 22nd Street Grill in Hermosa Beach. Yes, they have a patio. As does Uncle Bill's Pancake House in Manhattan Beach, although the food isn't as good (but still good enough). Unless you get there early, expect an exceptionally long wait at either place.
Ocean Diner in Hermosa. Not far, but uphill all the way from the beach; the way back is all down!
How is the 'new' Joes in Hermosa for pancakes?
Link to downtown MB business association. Maybe some other possibilities.
959 Aviation Blvd, Hermosa Beach, CA 90254
Uncle Bill's Pancake House
1305 Highland Ave, Manhattan Beach, CA 90266
1138 Highland Ave, Manhattan Beach, CA 90266