I would also suggest getting a SART and an EPIRB. A SART is a radar beacon, which shows up as a distinctive pattern on surrounding ships' radar displays, and requires no special receiving equipment. An EPIRB is a beacon that is locatable by satellite, so that's the fastest and most reliable way to get the attention of a rescue control centre. These three technologies are part of the GMDSS (Global Maritime Distress and Safety System), which means commercial ships and emergency services are by law required to carry and use equipment to receive their signals.
> If a vessel wishes to conduct a radiotelephony communication with the network, it is necessary to make initial contact via a DSC call. For safety or routine messages a shift to a working frequency is normally required.
When I did my training, they pushed DSC very hard.
Nit: You mention ch16 as being for distress traffic only, but my radio handbook also lists it for carrying urgency and safety messages, and as a routine calling channel (and then you move to a working channel and get out of the way).
Also: What crazy part of the world plays clutters ch16 with music?
As for music, last time I heard that was in the Java sea, but Americans aren't much better, making securité calls when moving their Bayliners, or the USCG with their incessant babble about irrelevant things.
Also, an AIS PLB, if the boat is equipped with AIS, is great, it's no bigger than a radio, and theoretically also triggers an alarm on any AIS capable vessel nearby. Without a life jacket, getting found again on the open sea in anything but calm conditions is difficult to imagine, considering how terribly hard it is to locate a head barely above water in the waves.
And everytime I have sailed in a blue water race, the entire crew wear self inflating harnesses that also contain a radio, gps, knife, dye, etc.... and often also a high vis swimmers cap. And the harness never comes off. Even while sleeping.