For the 3DS? No?
I have a feeling that Crystal should be coming to the 3DS, because;
Red/Blue/(Yellow) = GB (GBC). LeafGreen/FireRed = GBA
Gold Silver = GB (GBC, GBA). HeartGold/SoulSilver = DS
Crystal = GBC*** (GBA, DS) PassionCrystal = 3DS
See what I did there? Maybe it'd be best if they re-did Ruby and Sapphire for the 3DS, but I've concluded that you don't really need those games to complete the 718 pokedex of Pokemon X and Y, so...