Отримав непоганий список корисних плагінів для оптимізації роботи сайту на WordPress.
Тут і кешування, і оптимізація зображень, і швидкість завантаження сторінок…
Поки що збережу тут. Потім розберуся.

Caching:
https://wordpress.org/plugins/w3-total-cache/
https://wordpress.org/plugins/wp-fastest-cache/
https://wordpress.org/plugins/comet-cache/
https://wp-rocket.me/
https://wordpress.org/plugins/cache-enabler/
https://wordpress.org/plugins/speed-up-translation/
https://wordpress.org/plugins/speed-up-menu/

Image Optimization:
https://wordpress.org/plugins/ewww-image-optimizer-cloud/
https://wordpress.org/plugins/ewww-image-optimizer/
https://wordpress.org/plugins/imagify/
https://wordpress.org/plugins/imagerecycle-pdf-image-compression/

Minification:
https://wordpress.org/plugins/autoptimize/
https://github.com/futtta/autoptimize
https://wordpress.org/plugins/bwp-minify/

Google fonts condensing:
https://wordpress.org/plugins/google-webfont-optimizer/

Google Analytics Condensing:
https://wordpress.org/plugins/host-analyticsjs-local/

Plugin Organizer (stop plugins running on pages thry don’t need too)
https://wordpress.org/plugins/plugin-organizer/

Above the fold optimisation:
https://wordpress.org/plugins/above-the-fold-optimization/

Deferred JS:
https://wordpress.org/plugins/wp-deferred-javascripts/

Lazy Loading:
https://wordpress.org/plugins/lazy-load/
https://wordpress.org/plugins/rocket-lazy-load/
https://wordpress.org/plugins/speed-up-lazy-load/
https://wordpress.org/plugins/lazyload-woocommerce/
https://wordpress.org/plugins/a3-lazy-load/
https://wordpress.org/plugins/disqus-conditional-load/
https://wordpress.org/plugins/lazy-facebook-comments/