Good points. And I totally agree about the value of the vocals and the fact that just about any arranger from the past 12 years would work. But I actually do a few instrumentals every night and they are generally well received.
Most popular, bar none, is Last Date.
I have done a lot of instrumental Christmas songs.
Others I do from time to time are Watermelon Man, San Antonio Rose (Floyd Kramer version}, Sleepwalk, Honky-Tonk, Take Five, Unchained Melody (sax lead), In The Mood, Chattanooga Choo-Choo, Green Onions, Tequila, Sentimental Journey, Yakity Sax, Cherry Pink and Apple Blossom White, Theme from Dr. Zhivago, Raunchy, Wonderland By Night, Just A Closer Walk, When the Saints medley, Night Train, Rebel Rouser, Wipeout! Red River Rock, The Happy Organ, Never On Sunday, Malaquena. I know I'm forgetting some, but I'm really old.
Also Air Force song, Anchors Aweigh, Caissons, Marine's Hymn, for military occasions.
Several college songs such as Boomer Sooner, Tiger Rag, Rocky Top, depending on what team is in town.
By the way, do you know what is the one most requested song of all time for me? Happy Birthday. I do it 3 to 8 times per night. Lots of people come for special occasions.
Interesting thread, Chas!

Oh by the way, I was lying about doing Take Five and Malaquena. Can't do either of them justice for sure.