Hello Awesome Kathy!
Your plugin is the best! It's so elegant, simple, just great.
It would be even greater if it do almost the same for pages/posts.
Let me tell my use case:
I run a wholesale site with woocommerce. User must register using a custom form (formidable/register extension for more fields rather then email/password). They are set as "subscriber". After moderation, we change the role to "costumer".
With your plugin, I was able to hide the shop item from menu (among some really nice tweaks), but someone with a direct link still able to see my catalogs and prices, etc. Instead of seeing the original page content, they must see another pages content, like a registration link or login form.
I think there are several another use cases for this. I did some research and was not able to find a simple solution like Nav Menu Roles.