Not Bash, but zsh.

The host is there only because I'm usually logged in to 7 machines at once. The right prompt is the bare minimum path context, and the command # for easier !-re-execute; it disappears if the command gets long enough.

There's a bare minimum of cruft; no 2-line prompts, minimum verbosity in the prompt itself, because it's otherwise just noise that interferes with the output of whatever I'm doing and takes up space. It's especially important if I'm logged in via termux on my phone or something, where space is at a premium. What am I saying? Space is always at a premium.

$PS1 is

%{$fg[green]%}%m %{$fg[blue]%}»%{$reset_color%}

$RPROMPT is

%{$fg[green]%}%(5~|%-1~/…/%3~|%4~) %{$fg[yellow]%}%h%{$reset_color%}