Secret of Mana I highly believe will be ported over, should be soon and for the DS. I don't know about the other three games, maybe not popular enough for a remake.

By the way, did Enix stop making rpg's that aren't Dragon Quest? What happened to their other development teams that made all their other rpg's? Terranigma was a 8/10 game, it was great. The first part was very great!