If real time co-editing is not possible, you can at least show a warning pop-up that someone is currently working on a certain page. That would be better than blocking the whole site for everyone else.

Or open it even more with making it possible to define custom roles. Some sites do not need 4 different roles, but some might need 15 roles for different departments with fine-granular permissions set up.

For the easy set-up it would be good to have some pre-configured roles like it is now. But it should be possible to delete, rename, create new and change the permissions.

Sure, it is a complex task to construct a proper role and permissions management. But Webwave would be much more attractive to larger organizations with this feature. (especially if you manage to allow multiple simultaneous users some day: https://vote.webwave.me/communities/1/topics/83-multiple-simultaneous-editors)

This seems to be connected to this topic: https://vote.webwave.me/communities/1/topics/71-if-we-could-micro-manage-editors-and-users-role-more-specific