A Page Builder can be used with WishList Member Add-ons. The course library, modules and lessons pages are standard WordPress custom post types.
That means any Page Builder that uses that standard WordPress architecture should work with courses in the WishList Member Add-ons plugin. So you have the option of designing your individual pages using a Page Builder.
There is an important detail to keep in mind when using WishList Member Add-ons and a Page Builder.
Courses, Lessons and Modules (and Quizzes) typically need to be enabled within the post types section of the Page Builder. This allows for those sections to be edited using a Page Builder.
You would need to enable these options when using an option like Elementor, Oxygen, Divi, Beaver Builder, etc. are these options are usually disabled by by default.
We have included examples of where these can be enabled in Elementor, Divi and Beaver Builder below. Most Page Builders will have a similar section to set Post Types.
Elementor > Settings > General section
Divi > Theme Options > Builder > Post Type Integration section
WordPress Settings > Beaver Builder > Post Types section