Once again I've used the reusable Text Blocks to isolate and/or reuse moderately large blocks of HTML content.
I use the Classic WordPress editor, so the text blocks keep my HTML from getting too unwieldy. For example if I'm coding a two-column layout by hand, I can put the layout code in the page but put the columns content into Text Blocks.
Things I create reusable Text Blocks for include PayPal buttons and a schedule that appears at two places within the website. Isolating code to Text Blocks also reduces the chance of HTML errors from ruining the entire page, especially if clients are editing the pages themselves.
I like that I can use the block name within the shortcode.