In gnome there’s dconf

Personally, I think methanation may be promising, since you can use the existing infrastructure.

Slugs do not work that way! Good night!

Insane Clown Posse would like to have a word with you

I use Fira Code, but any font patched with Nerd Fonts will do.

Personally, I like starship, and how it’s consistent across different shells. I mostly use defaults, but with line break before command.