I think a big issue is also a limitation of technology/scope. As with any piece of fiction, not everything can be described (characterisation of sorrows for example) and so some stuff must be left up to ones own interpretation/imagination. How one fills in the blanks heavily influences how Joshua Graham is perceived. It's a very good point about him using the Dead Horses as nothing more than a tool for his own salvation, I hadn't really thought of that.
I think I've also been very dismissive of the games critique of Graham's methods, because it reeks of "both sides" centrism to me, but that is in large part me treating metatext as text and that's not really fair.