Graphics
Graphical dependencies (i.e. object files) take up a lot of space, and saving them in states would not be practical. Fortunately, they mostly contain static data that never changes, and can plainly be loaded from the rom when needed. But there are some graphical effects that modify these files, and gz does not account for this. Specifically, some dissolving effects are known to modify textures, which can cause them to look odd after a state load. These issues are purely aesthetic.