Honestly, nostalgia works really well. Too well.
A link between worlds was too successful despite ruining the canon of the Zelda timeline, and also banking on the exact same world, and story.
The biggest difference with Pokemon and Zelda is that each title is extremely different from the last. There is not one title that fully takes from the last.
For Pokemon, it has the same formula because thats what makes Pokemon "Pokemon". Adding some side games, or expanding the world and story, but at its core its the same. With that said, if Gamefreak remade a Pokemon Red/Blue/Yellow with the new designs and specks of XY/ORAS, then it would be a great game. I dont doubt it will be incredibly successful.
We get to experience Kanto for the first time in the current graphics. Some areas will feel completely new, and amazing. There's plenty of room to bank on nostalgia, just as much for new players and old. But like before, i think it shouldn't just be red/blue/yellow alone.
I genuinely believe that Red/Blue remake would be more successful if their merged with Gold/Silver. I call it RedGold, BlueSilver. And there can even be an interquel similar to Final Fantasy: The Complete Collection.