Excess flour in banneton after proofing
I have several bannetons (also called brotforms).  Two are wicker and 2 are cane (you can also find them made from wood pulp).  I simply use a small, stiff pastry brush to clean away any flour left behind.  Sometimes I find it helpful to leave it out overnight so the flour dries and it is easier to brush away.  I have even given the canes a quick rinse but I do make sure to thoroughly dry before storing.  In addition to rice flour, I have used AP and bread flour with success.

With the wicker ones, sometimes I use food grade linen that I flour and line the banneton with to proof the bread.  I have also used plastic wrap that has a light spray of olive oil.  These two methods eliminate the need to flour the banneton.  It just depends on my mood and the surface finish I want on the baked loaf.