Adding Custom Post Types, especially multiple types in the same project, involves a great deal of copying and pasting. Additionally, most implementations that use classes end up using them as a makeshift namespace that goes against proper object-oriented programming. I’ve developed some helper classes that make it easier to register custom post types and their taxonomies as well as simplify the development of admin-side customizations that are typically made with post types in a way that is consistent with proper OOP.
So much of the post type registration process has been automated that you can create a Custom Post Type and related Taxonomy in as little as four lines of code.
I’ve made the repository available on GitHub along with documentation on its potential uses. If anyone sees ways to improve the classes, I welcome feedback and contributions.