I always remove sudo from my laptops, su works fine inside tmux. Since the laptop screen is locked when I'm away, the tmux session (with root) can stay active for weeks, so not much typing the root pw.
My everyday remote machines all have an ssh-key for root (and a very complex password that I have printed on a paper at home).
I use pwgen -sync "${1:-42}" -1
I have a special 'goroot' script which launches an xterm in a white-on-black color-scheme and requires the root password, as distinct from my normal-user xterm script which launches xterm in a black-on-white color-scheme.
Oh, how long?? 9 characters.
I see this as both good and bad - users should know their own private credential (rather than the shared "secret" root passwd), but as it's a password they use regularly (potentially multiple times a day), it's easy for people to use something less secure than they otherwise would for "root".