1. A little ginger goes a very long way and can cover the kombucha flavour. If you like that, it's perfect. Otherwise you can use less or take it out after it gets to the right flavour.
2. More orange juice means more sweet but can also be fermented if you leave it longer.
3. If a scoby forms in the orange floating on top, then filter out the juice from underneath before serving but that means it was a safe success!