Jeff,
Most of his work was in big bands where he often had other talented trombonists around. For example, the equally overlooked trombonist Sandy Williams played alongside Jones with Chick Webb and Coleman Hawkins.
Jones didn't record much following his stints with Ellington, where there again were other fine (and more often featured) trombone soloists in the band.
There are some small group sides on which you get a better chance to hear him, such as the Armstrong date that you mentioned. Another is the Benny Morton Trombone Choir session for Keynote from 1944 where you get to hear Benny Morton, Vic Dickenson, Bill Harris, and Jones. Wonderful date.
Another small group session is the Morton (Jelly Roll) Seven date from 1940 on General (later on Commodore).