One quick thought, I assumed that your concert was in English. If not (or for the sake of variety) why not throw in a couple of German songs just to see audience reaction, you already have Lili Marlene, why not add the "Panzerleid" (remember that scene in - I think - "Battle of the Bulge") or two Great War songs which still held favour, "Wacht am Rheine" or "Marineleid" ("Wir fahren gegen England") (My apologies if the spelling is incorrect, I have enough trouble in English, let alone German).

Good Luck

Tom