Opportunities: clear trash from tables as it becomes available.
If you are the proprietor of the restaurant its important you build relationships with your patrons. Don't hide in the back and never never walk by a table without introducing yourself.
Open the sunshades if the sun isn't beating down in the windows. Makes for better atmosphere. Plus it allows those driving by to peek inside.
Pay a professional for a proper menu design and and have have a quality menu printed. You only make a good first impression once.