That list is pretty good. I don't know what you think but, I find the usually excellent Peter Underwood's list a bit unhelpful:
Atmospheric Photo Ghost
Historical or Traditional Ghost
Anniv Ghost
Modern Ghosts
Ghost of the Living
Crisis or Death Bed Vision
Family Ghosts
Haunted Objects
Fraudulent Ghoat
Survival After Death
and, as Cufflink correctly concludes with, Mixed Hauntings.
The Spencer list could have included phantom sounds and smells, elementals and folk memories; it is useful in that it classifies ghosts as to how they operate. There could be an endless list of types of ghost as they appear: Monk, White Lady, Horseman, Black Dog, King X and Queen Y..... (Even invisible cat killer or wardrobe inhabitant!

).
Also, Spencer's Doubles, Bi's and Doppels could be separated and added to by ghosts of the living. Any human figure apparition could be said to be a doppelganger?