Well, if you don't mind coming out of the city centre, we could meet at Coffee Angel at Canonmills/Brandon Terrace - they do soups and sarnies and salads and are open till 7pm. I tend to try and avoid the Mile, North and South Bridge and points south, George IV Bridge, Forest Row, Princes and George St at this time of year, since everywhere is usually mobbed. The 23 and 27 buses will get you there and back if you don't want to walk or else are lazy like me.