Customize website appearance for various user roles after logged in.
Hey you should create a backend editor extension for layers. When you open customize.php there should be options for membership/ account types and how to mange them (i.e. customizing the side panel objects they see when logged in, and their default landing page or a custom dashboard managed by admins). Make their logins a certain page that has a completely different menu (and no wp-admin sidebar) or option to add a custom menu once logged in as a certain user role. possibly add a new page template button.
I have more ideas if you want to collaborate. For extensions to help me use it and make the best possible layers. I love it and it helps me so much and there are a few flaws (missing buttons and options for extra customization) but I love your theme.
Possible Answers to Your Question:
I have recategorized this as a Feature Request in case someone wants to take this on. It is not something the Layers Team will likely do as this is very very complicated from a dev perspective, as WordPress core capabilities only give Customizer control to admins. What you are looking for above is already possible with the Admin Menu Editor or Justin Tadlock’s Members plugin, the function of which is really best left out of the customizer experience since it is not configuring visual detail on the frontend of your site.