He wrote a one-man show, David Mills – His Poetry and Songs, which premiered in Toronto in 1989 and then toured to numerous Canadian cities in the early 1990s.
As a composer he has written a cantata, Vision of Peace to texts from the Book of Isaiah, and several art songs to the poetry of Pauline Johnson and Robert Browning.
In a 1987 review, music critic Pauline Durichen described his voice as "displaying vibrant deep-range control... and at times a soulful sweetness at heights where few basses dare linger".
In 1954 he performed the bass solos in Ludwig van Beethoven's rarely heard 1814 cantata Der glorreiche Augenblick with conductor Emil Gartner and the Toronto Jewish Folk Choir.
[1] Mills studied voice at the University of Regina (UR) with Alicia Birkett from 1947 to 1949, during which time he performed on the Canadian radio stations CKRM and CKCK-FM and was heavily involved with the music programs at a number of churches.