Nice built in. First I would consider adding lighting to the inside top shelf to help brighten it up. (See pics.) You have a lot of dark small items. I would remove some of them and remove the unframed photos. You could rotate your items every few months. Move the larger heavier looking books to the lower shelves.You might consider painting or wallpapering the back of the cabinet to brighten it up as well.
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Decorating Bookcases
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