The 3DS still can't quite run exact GameCube level visuals. You could do something like Skyward Sword on the 3DS, but it would have to be downgraded in a lot of ways.
3DS is better off coping with a 3D Zelda like Ocarina of Time but enhancing that instead.
This will change with the next Nintendo handheld though, it will be able to run a 3D Zelda that significantly would outperform even the most recent Skyward Sword with ease.
You start to reach a level of graphics where I think it's "satisfactory" to a lot of people.







