I would recommend starting with FreeBSD. They have a handbook on their website that explains everything you would need to know to get set up and get an idea about how everything works. You could kinda compare it to the Arch wiki.
A vast majority of things will be very familiar to you as a linux user and the repos/ports have almost anything you could need. A big difference is going to be the init system. It is more like Open-RC and runit compared to SystemD. It is based on scripts and very easy to use when you get the hang of it.
The most obvious drawback is the lack of support for 802.11ac (it is in the works and you can use something called wifibox to use linux wifi drivers).
CMUS as a music player. Clean interface, lightning fast and plays anything. I use it daily.