It would be helpful to have a guide to this for people running a 'low audience website' where there is no CDN or Varnish, just some Apache or Nginx server on a slow-ish but cheap VPS.

For a local business or community, e.g. an arts group with a Wordpress style site, there are many common problems, they might not need a full CDN, just serving media files from a cookieless subdomain gets their site up to acceptable speed cutting the header overhead considerably.

Purging the useless headers might also include getting rid of pointless 'meta keywords' and what not.

The tips given here could be really suited to this type of simple work to get a site vaguely performant. How to do it with common little guy server setups could really help.