That's tough! Owners always see space from the point of view that used for more tables it makes money but when used for the kitchen it costs money. It's obviously very difficult to crank out a high volume of food from a small kitchen. Obviously anyone you can hold hot is a plus. Maybe crepes made ahead with a filling that you can hold hot? Maybe hold sides hot (eg baked potatoes, mash, roasted veggies or even rice for short periods) along with poached fish. You could keep a pan of court bouillon hot on the flat top and poach quite a bit of fish at once. I know you said oven space is at a premium but having fish en papillote is another way of cranking out a pretty good volume with minimal space. Various stews and Bouillabaisse-type items could also be held hot.
Deep friend entrees might also help if you have four decent sized fryers. Again, not really sure what your check average is or what types of things will sell but battered and friend fish and shrimp items might work for you. Using the flat top for fish might be viable if you don't do too many sandwiches at a time.
Deep friend entrees might also help if you have four decent sized fryers. Again, not really sure what your check average is or what types of things will sell but battered and friend fish and shrimp items might work for you. Using the flat top for fish might be viable if you don't do too many sandwiches at a time.