Yeah there is just so much choice now with Linux audio, all of those above are good for beginners. My son regularly uses Guitarix and hydrogen when he is working on something new, before the band get together with the real hardware. Ardour is a great introductory DAW that people can learn before they move on to something like Reaper or pro tools.
With the introduction of pipewire as well recently, the whole Alsa, jack, pulse nightmare is rapidly looking like a thing of the past.
The deck uses PDC?, basically it has a negotiated power draw. The charger is around 2-2.5Am(I can’t remember anything today), 45W and can range from 5-15 volts. I’ve had usb hubs with memory sticks/cards, keyboard, hdmi and external ssd all plugged in with zero issues, although if I use my usb-c extension cable I need to run it from the power cable to the hub and not the hub to the deck as things get very flakey configured with the second option.