Get rid of older perfumes: after a while, most perfumes tend to not have the same scent anymore. If a perfume has gone bad/expired, it must have been one you didn't use that much while it was still good so it's one to get rid of
Only display your favorite bottles: some of my favorite scents (like winter candy apple and all of the Bath and Body Works scents) don't come in fancy or glass bottles, so I tend to keep them in my bathroom or in a drawer and not on my display tray.
Use perfume as decor: I have my perfume tray on a bookshelf in my built-ins and it makes the shelf look full, decorated and it's a nice piece to have displayed. Displays for perfume also look pretty in a bathroom on a tray similar too