Restricting access to text based on user

Hi

I hope this community can assist with.

A user wants to publish a large amount of chaptered text to either a document file (word etc.) or a sharepoint page. The User would prefer instant access and not to have open a document.

The problem is that some of the textual content needs to be restricted to a higher group level.
I need to employ versioning, Retention and bookmarks.

I suppose I could create a Sharepoint page, add content webparts within the page use Audience and bookmarks. However how will this work with versioning and retention?

Ideally I'd rather use Document libaries as it will retain the overall structure but dont think I can restrict user from certain parts.

I'm on SharePoint Standard.