Why remake these great games if people can also play the originals? Both A Link of the Past and Majora's Mask are already available on the Wii's Virtual Console. I assume that also means they will be playable on the WiiU and could easily be added to the VC of the 3DS (or maybe they already are, I don't own a 3DS).
Furthermore, A Link to the Past already has a remake (or glorified port, if you will) for the Gameboy Advance.
So yeah, they should concentrate on a new Zelda. If they really want to remake something, I think they'd better pick a game not many people have played due to limited availability (e.g. Earthbound); or make a remake that truly adds something to an original that was too difficult for most audiences and/or had some major design flaws (Metroid: Zero Mission is an excellent example of such a remake, in my opinion).