A simple solution of cold wallet distributed in multiple wallets, with multiple good UTXOs, in multiple locations. never keep all the stash in only one place / wallet. Use also the 3 levels stash method.

I don't. Inheritance for me is begging, is not PoW. If they want my sats they must work hard to earn it from me, during my life. If they are not able to do that, then why they should deserve my sats? Each one should have his own stash and take care of it separately. You lose it? You get what you fucking deserve. I know it sounds harsh for many, but this is the truth. Bitcoin is about being responsible for your own actions. Don't be a pussy. I don't give a shit what will happen after I die. I am dead anyways and I cannot change anything.

If you let them know that there's an inheritance of x amount of BTC they will do anything they can so you will die soon and take your sats. So why would I let that happen? Let them instead prove me with hard work that they can earn and deserve those sats.