its still probably a couple of weeks before i will focus on skinning, bur i want to put it out there now re: thoughts on how skinning should be changed because of the flexible way panels can be configured eg. before you might use a range of colors for the left sidebar because you could be sure the left navigator and library explorer could only be docked in the left sidebar and there was no "left main panel". Now many new elements can be docked in various panels.
My thoughts are simply to have an optional default that applies to any element docked in a panel (left sidebar, left-main panel, main panel, right-main panel etc) but to allow an override color scheme for each element as well. There would still be view specific settings for track details, artwork for the main panel as now.
I know some of you want a tab based layout for when elements are overlayed. I will probably make that available as a musicbee setting rather than a skin setting