Variety is COOL. On a 4 hour restaurant job, I do nylon string
instrumentals, acoustic guitar with vocals, large jazz guitar instrumentals, plain piano solos, just piano/vocals, arranger and XB-2 Hammond with left-handed bass. Sometimes, I even bring a double-neck end play a few solos with it.
Just keys is a really nice break or way to start a set.
GO FOR IT!
R.