Secret of Mana
The world of Mana is interesting, sure, but what can you do with it other than tell the story that's already been told? What's the hook? How do you plan on capturing that bright, colorful, and fantastic atmosphere while retaining the dark and sometimes disturbing edge on the story?
What system do you want to use?
What story do you want to tell and how do you want to tell it?
Secret of Mana is cool, and it has a lot of potential. So do flour, eggs, butter, and sugar, but they're not that great without the plan to make pound cake.