My thought was they had to have a tremendous take out business given the location. The one thin I did notice tho was the profit margine was 10%. Now I know it's not up there with some of the other industries like ummm errrr uhhhhhh..... Oil. where the margine is close to ummm...... a million %

But 10% is pretty respectable.
Yet you are correct that inorder to increase sales and profit something has to be stilmulated. I'd go for the Take-out sales or add delivery with-in a certain area. But then again a 200 item menu. That may be exactly what is the problem. Granted they have a strong and loyal local clientele but any new visitors might be just a bit overwhelemed with that menu.
I'd say Scale down to the top 100, special the more requested items on a rotation (and not 20-30 at a time) and go from there.