I find Tachyons better than Tailwind. Much shorter class names and a thought-through system which makes it hard to make bad design. Also setup (there's none) is easier than with Tailwind.
Tachyons certainly is a good alternative. The system is as thought-through as Tailwind's, though there certainly is a bigger ecosystem (tutorials, videos, components) for Tailwind. Also I found it easier to customize and extend Tailwind. And if I don't plan to customize I just use the CDN version which is just one-line. Again, Tachyons is a perfect contender and if Tailwind does not convince you for whatever reason, have a look at Tachyons which has a slightly different philosophy.
My take on this customization: Once you need more use css-in-js libs like emotion. But maybe you like to elaborate with an example you custom stuff works in Tailwind?