ThemeShaper.com has a good article on using WordPress as a CMS and lists a few plugins that come in handy for this: Use WordPress As a CMS: Plugins, The Bare Minimum
I have a few recommendations of my own to add to the list.
- RSS Control is a plugin that gives you more fine-grained control of the WordPress RSS feeds.
- Simple Sitemap makes it possible to add an HTML sitemap to your website. Make a page and add one of the Simple Sitemap blocks in the Gutenberg editor.
- Simple Page Ordering is a plugin that makes it easy to visually arrange the order of your pages.
- Category Order — while the above plugin arranges the order of your “pages”, this plugin arranges the order of your blog “categories” — which is handy if you are using your blog categories in an unusual way while using WordPress as a CMS — Category Order can be found near the bottom of the linked page here.
- Obfuscate E-mail is a plugin I find I need on most WordPress powered sites I setup — you can post email addresses as links and this plugin will obscure the address in the html so as to confuse spammer bots.
- Role Manager plugin gives fine control over which users have access to what features on your WordPress install.
- Search Unleashed – Advanced WordPress searches with highlighting as well as searching of pages and posts.