You're welcome, I hope it helps! To preface this, I think Ubuntu 20 comes with good font rendering options by default, so my suggestions are mostly unnecessary. I just wanted to experiment to see if I was missing anything. All the options I'm referencing are explained in detail in this blog post (e.g., subpixel rendering and lcd filtering), they're all just configuration options in the freetype2 font renderer.

I found that the Arch Linux wiki page (https://wiki.archlinux.org/index.php/Font_configuration) is helpful because it applies to other distributions like Ubuntu, and provides example configuration files. (https://wiki.archlinux.org/index.php/Font_configuration/Exam...)