I wish I had an answer for you, when I put all my fabric on comic boards, I was very pleased with myself. Could see what I had and easily access it from the shelf instead of stacks or bins. But ran into the same questions as you plus some.
My biggest problem (and still is) what to do with all the fat quarters! Still looking for a good storage solution. For now they are in those big Artbin plastic containers on a shelf. I am just trying to use them up and I no longer buy fat quarters! If I like a fabric enough to buy it, I just buy a yard and be done with it. But basically I just quit buying fabric last year and now only buy absolutely what I need to finish a project.
Organizing scraps??? I did cut some of the smaller pieces into strips for string quilts and got them organized by color.
Hopefully someone will be able to provide an answer for us all.