Drupal and 'access'

As a mental health nurse, informatics enthusiast and website developer, I have a multi-fold appreciation of the meanings of 'access-ability':

1. Cognitive access to buildings/facilities
2. Physical access to buildings/facilities
3. User access as per human-computer (device!) interface
4. User access to content on a website - beyond pure interface considerations

Item #4 has been at the forefront of my mind for a few days, as most serious sites/blogs require users to create an account. This can be a pain in the form of yet another log-in sequence to remember (in case the browser forgets). My fear is that visitors might reason that "I only want to see whether stag beetles are thriving where I live ...".

It is possible that the future structure of the new site could hide content that visitors really wish to access. I could argue that if visitors need the text that much, then they will create an account.

There must be a logical way to do this? Sketching the content and whether it is public or private is quite critical at this stage. It will affect the roles adopted within the new site. My initial thoughts are encouraging, because they suggest that the bulk of the content - introductory material - can remain accessible to anonymous users (casual visitors). So, here is grandiose "take 1":

PUBLIC anonymous :: PRIVATE registered users
Brian's original notes :: Blog - edit own blog
Chronology :: Book
Biographies - BH, PJ and You!? :: Education - Scheme of Work; Session Plans
Informatics (updated!) :: h2cm and Philosophy
Podcasts :: MCQ - other questions
Resources - templates; reference pack ::

There's a few more possibilities, but we'll save them for another time: Manchester beckons tomorrow tonight - so back to Drupe!