the system really good and looks cover most of the requirement for any restaurant or delivery business.
from my experience as an ex IT and software designer, there are some points I would like to mention.
1- in the delivery section, when you build delivery area I prefer and many restaurant owners to add a postcode area for example like my restaurant postcode BS3 1BH so I am willing to deliver to BS3 if you understand the UK postcode the area specified by the first part of the postcode.
2- on the frontend, there is a module with " Order delicious food online" it's not gone when you make the website single location.
3- when I go to the menu the default desighn looks like just-eat its good but