I’m not an optimization expert nor am I a WP power user but I have been using the platform for over ten years. I have a strong preference for plugins that are lightweight, easy-to-implement and configure, and have a clean removal (plugins which leave artifacts are a huge pet peeve of mine). Here’s a list of my must-have plugins for almost all WordPress installations.
My complaints with WordFence surround it’s initially annoying push for upgrading to the premium version. You can dismiss/hide those, though, which leaves you with a pretty effective solution at thwarting most low-end abusive crawlers/sniffers. The highlight is the threshold with auto-block feature which allows you to block traffic if activity breaches certain thresholds. It just makes things easy.
Although not my area of interest, it’s handy. Instant Images pulls free-to-use (under the CC0 license) images from UnSplash directly into your WordPress media library. It saves a few clicks and makes things easier when in need for stock images.
Velocity is a nifty plugin that allows you to embed YouTube/Vimeo/SoundCloud media without loading the heavy iframes/JS libraries until the user engages with the media. This saves a ton on overall load time/size. It also allows you to set a custom preview image for your embedded media so that’s a small plus. Using this plugin, I reduced my page load size from 1.73mb to 634kb and reduced the number of requests onload from 89 to 59 — this is a 1 second decrease in pageload for devices on 3G networks!
commonWP is a plugin which uses the jsDelivr CDN for common WordPress JS files. It’s super easy and low-risk to implement thanks to really well thought out work from the creator. I hope this expands to CSS files in the near future.
Enlighter is an easy-to-use syntax highlighter that supports most languages. While there are several syntax highlighters out there, I like this one in particular for it’s easily modifiable CSS and clean editor integration.
WP Mail SMTP
As the name suggests, this plugin enables easy use of SMTP for mail on your WordPress installation. No need to go deeper than your WP-Admin pages to configure mail for your WordPress installation. The downside is that it was recently acquired by WPForms so I’m guessing it’ll be turned into an intrusive, premium-hocking version in the near future.