The only detailed information I have close at hand is (read mm/dd/yyyy):
Wheeler's Cavalry Corps, Army of Tennessee (04/06/1864) -- 9 on staff
1st Cavalry Brigade (BG Humes), 4th Cavalry Division, Army of Tennessee (03/01/1864) -- 4 on brigade staff; by 03/15/1864 there were 7 on staff
2nd Cavalry Brigade (BG Davidson), 1st Cavalry Division, Army of Tennessee (03/04/1864) -- 10 on Brigade staff
3rd District (BG M.L. Smith, Dept. of South Mississippi and East Louisiana (MG Van Dorn) (07/09/1862) -- 14 officers and 1 enlisted on staff
3rd Subdistrict (BG M.L. Smith), Dept. of the Mississippi (MG Van Dorn) (08/27/1862) -- 9 officers and 1 enlisted on staff
4th Subdepartment of Mississippi (BG Villipique) (Jun 1862) -- 9 on staff
I got this information from a collection of copies of various Confederate Army reports that are in the collection of the Mississippi Department of Archives and History. The other reports, primarily of portions of the Army of Tennessee in early 1864, had detailed breakdowns of personnel and weapons, some of which I copied. I seem to recall that the corps, division, and brigade staffs were detailed but I didn't copy them at the time.
For generalities, Paddy Griffith's Battle in the Civil War states that a brigade staff might have a quartermaster general, a commissary general, an adjutant general, plus some aides and orderlies. Higher staffs would have more of each sort and might include an inspector general, a provost marshal, judge advocate, topographer, and signals, as well as cavalry, artillery, and engineer staff officers (especially at corps level).
Hope this helps.
Jim