who is the target? i would suppose the 13yrs old working with his dad as noticed in another thread would suit for an example. it would apply to me as well, a past middle aged with zero linux but determined to set mineos up for his young girls. the time it took to set up vmware, vsphere, mineos and forge servers (a ftb server was the first one) was huge and took alot of study time.
not for the faint hearted, to say the least.
so skipping the basics as i have described above and as you propose could cover topics less traveled like how and when to use/ enable and the dangers of nano, webmin, root log on and the iptables (all things disabled by default) for example.
some basic commands used at the terminal as root (enabled by default) and what they do, update java7 to java8 for example or updating keyring or archive-keyring.
cover the difference and when to use apt-get update, upgrade and dist-upgrade, how to update node and when.
stuff like that and i suppose there is more because of the different distros of mineos still in use today, hosted severs, dedicated servers and or old pc/ laptops conversions, python, linux, centos, cherry pi or whatever flavor of each and how installed.
mine was so simple because i just loaded the node.js mineos iso into the vm cd and mineos auto ran, the install was as simple as it can possibly ever get and i saw a tutorial by sir hexparrot, a little out of date but it helped. a vanilla sever also as simple as it gets.
so tutorials on what forge (custom and pre-configured servers), spigot, bungee (i have no idea about these) and mc pe servers will accomplish.
finally, how to set up your own neighborhood commercial server so one can charge all the hood rats to log on, rotf!
actually i meant how to set up a small server for remote family and friends like port forwarding, firewall tunneling and server security.