I prefer most things stored behind doors, it will look least cluttered. Some of us do have some nice books or some nice collections we like to show off. There are a few ways to arrange your collectibles in a way so it will look organized. If you are displaying books, arrange them by category. Another way to do it is by size or color. If you are a collector of things, display them by what I call "form language" it's a term we use in Sweden to describe things that have the same shapes or materials. I think it looks best if you separate it by materials, where you cluster all your ceramics in one area, all your glass in one... and so on.
I love this idea of hanging a ladder on the wall, using it as a bookcase! I think it would stand out even more if it was painted in a shiny bright color like grass green or bright yellow!