Ashley - Right, that makes sense. One more question, if you don't mind - I wonder if there's a way to generate mipmaps by isolating each animation frame to its own texture when creating the mipmaps (by either cropping the rest off or copying/pasting that singular animation frame to a new texture, then resizing it, then pasting it back to the spritesheet)? Then it wouldn't average pixels from adjacent images because there wouldn't be any.
Since the problem only happens on export, and sprite sheets only happen on export, having the textures isolated solves the issue, so I'm basically wondering if you can make that isolating behavior happen from a spritesheet at mipmap generation time.
Or, as newt said, perhaps giving us an option to turn sprite sheets off would be optimal for some users? Or would that essentially make no difference by resulting in the same amount of memory used as putting them all in power of 2 locations? I guess if that's the case then the only difference would be more file requests which is a disadvantage.