Yep. A pointer is a memory range, but it supports a cast operation that allows you to change the pointer type, and therefore the end address. I think we agree, right? :)
Hmm, yeah, void pointers are weird. I'd be inclined to say that its start and end address are the same and it's a range over 0 bytes of memory, and the fact that dereferencing fails is an artifact of the dereferencing operation itself... but I don't know enough about void pointer voodoo to know whether that's actually a consistent interpretation.