Just published a tool I built to improve inspecting OCI container image layouts : https://github.com/project-machine/oci-viewer
It's a niche tool, but if you need it, it's really handy.
It's a quick way to see what images and artifacts are in a given layout (or set of layouts), and which base layers they do or do not share...
Also lets you search through tag names/layer hashes and annotation contents to find an image you want in a big layout.