If the public key was the QR code on the front of the watch, and then on the back of the inside of the casing, you could engrave the private key, so it can be unscrewed and retrieved without touching the movements, if you included the tool to unscrew the back of the watch with the purchase it would be pretty cool. Just my two cents. I love the idea.
I really like this idea, but have 2 concerns:
What if I need the watch serviced? I am going to have to trust someone with my private keys. (Maybe your idea of providing the tool to unscrew the back might work, if the back had the key engraved (even better if it were encased in a hologram).
Also, I agree I like the Bitcoin reference on the watch, but if the keys are on the inside and it is known, it would be a theft target.
I still prefer 2 options:
Provide a corresponding private key on an opendime or some other device similar to what the high end Vanguard watches do:
https://www.franckmuller.com/news/vanguard-encrypto-limited-editionHave it in a ring or some other accessory that does not have a "Bitcoin" logo at all, that you can keep separately and or decide to take with.
Just my 2 cents.
Thanks!