This list was copied from Mike Sass’ Website Component Checklist. I’ve added things I thought would be useful.

• Custom 404 page
• 88x31 button
• /About page
• AI manifesto
• ai.txt
• Activity feed
• Architecture.md
• Archives page
• Blog page
• Blogroll
• /Carry page
• Change Log
• change-password
• Comments (for blog posts)
• /Defaults page
• Disclaimer
• dnt
• dnt-policy.txt
• Donation page
• Email link
• /Favorites page
• Feeds page
• Guestbook
• Hello page ( info)
• Home page
• humans.txt
• Ideas page
• indieweb.txt
• Interests page
• Library
• License
• Light/Dark-mode toggle
• Links to social media
• Museum page
• Nope page
• Notes
• Now page
• “On This Day” button
• PGP key
• Privacy policy
• Privacy.txt
• pubvendors.json
• “Random” / “Surprise me” button
• Resume page
• Roadmap page
• robots.txt
• RSS feeds
• Search
• security.txt
• Site Map
• Site Statistics
• Style guide page
• Tags
• TIL page
• Uses page
• Values page
• Webfinger
• Webmention, send
• Webmention, receive
• Webring (Webring Enthusiasts) or IndieWebRing