My initial view of these two death cards may be different from the views expressed to this point. I see "death" here depicted as two different points in time.
"Death on a horse" suggests to me that Death is here. "Death as a skeleton" suggests to me that the actual point of Death as just passed. I'll explain.
Death-on-a-horse is now "here." We see terrible things relative to his presence -- the gloomy background, horribleness (as seen in the faces peeking out at us), a snake among the lava-like rocks. We fear what we will now experience.
Death-as-a-skeleton seems to be a scene just after the point of death. We see grey, spirit-like people. We also see colorful people, although they seem sad and anxious. The grey people have died and realize that their environment has changed, the people with color (living) miss them and realize that their enviornment has changed. Death and the hooded figures who seem to overlook the transition move among the dead and the living.
In both cards there is a lighted pathway that may be available. It rises above the scene of death and suggests a form of measurement is inherent within it. Is this a call to judgement? A path away from the experience of dying?
Which death card is more appropriate -- is it really appropriate to have both cards within the deck? What dying situation might a querent find themselves facing -- one of impending death or transition, or that coping with a death that has ocurred? Would both cards appearing in a reading suggest the experience, the problem, the solution all at once? Will our individual views on death, life and the afterlife permit us to cope with two death cards or use them to better help a querent? There is a lot to think about here. Dave.