Aibetsu, first of all I think your hair looksgreat in that picture.
Second, I had the same problem with flatness at the roots and I've been experimenting with some different ways of solving it. Difusing upside down at the roots really helps me. Also, I never thought I could shower at night since when I sleep my hair gets all messed up like you described. I've started putting it up in a very high ponytail on the top of my head (I found that recommended on this site) with a satin scrunchy before bed, and in the morning when I take it down the curls are still there and sometimes looking even better. You could try that to eliminate brushing altogether.