I usually use two different flour mixes unless a specific recipe calls for different combinations. 
Mix A
The first is the traditional rice flour mix based on Bette Hagman's mix. 
2 parts rice flour - I use both brown and white
2/3 part potato starch
1/3 part tapioca starch
I use this mix for cakes and scones. 
Mix B
The second is a mix that I've altered slightly from Annalise Roberts Bread Flour Mix B. 
It consists of
1/3 part millet
1/3 part sorghum
1/6 part corn starch
1/6 part potato starch
1/6 part tapioca starch
It's rice flour free but I find when making my English Muffin Loaf it does call for 3 cups of flour so I often add a little rice flour mix to even it out. 
 
