It would make sense to call the 3rd version to Black and White Grey because each series of games within a generation are all linked.
Red, Blue, Yellow - Primary Colours (Obviously in Japan there was Green, so you could say the most basic colours)
Gold, Silver and Crystal -...
I don't understand how there could be more hints to an Emerald remake then what there are to Ruby and Sapphire's remakes. Either way if they did remake Ruby and Sapphire, they would most likely include most of the features introuduced in Emerald anyway, like the Battle Frontier for example.