Hi Karen,
strictly on-topic, regarding the subject "which lau distro is more
commandline friendly?"
All well known Linux distros, including the mentioned audio distros
provide easy access to the command line. All allow to access a
terminal and all default to bash for the login shell. From this point of
view, it makes no difference which distro you chose from the well known
distros, since from this point of view all those distros and all their
releases are "command line friendly".
From the point of view, what distro to chose, to compile software from
upstream, there are differences, since distros have different policies.
I don't know the defaults of the audio distros you mentioned, however,
a Debian based audio distro likely could be used with the Debian sid
repository and apt-pinning, while an Ubuntu LTS based distro just
provides backports, IOW a Debian based audio distro might be more
"command line friendly", if you want to compile software from upstream.
As far as I'm concerned, I use Ubuntu Studio and perhaps will add a
KXStudio PPA and I also use Arch Audio. I stay away from Debian and
especially from Debian derivatives.
Assumed you want to run jackd without running X, there might be
differences between defaults of distros either, but unlikely between an
Ubuntu based and a Debian based distro, since Debian is upstream for
Ubuntu. You'll notice that the Debian tracker mentions the Ubuntu
packages too, e.g. for jack2,
https://tracker.debian.org/pkg/jackd2.
Hth,
Ralf