Inheritance/disaster planning with hardware wallets

I hope this thread will be interesting to everyone interested in the technical side of Bitcoin, as I suspect that anyone reading /r/bitcoin in 2020 is going to need this information by 2025. If you don't know the answer, can you send it to someone who might?

Like many people here I am in a fortunate position and have considerable value in BTC, controlled with a hardware wallet.

There are two situations I am planning for:

1. My unexpected death (or incapacitation)
2. A severe fire which destroys my home

I need to securely store my backup so that there is not a single point of failure, or single point of trust.

I think that a multisig address is not suitable:

• If I move the coins out of that specific address, the system fails
• Trustees can see how much money I have, and what I am spending
• It is very difficult to set this up with Trezor and I keep having technical issues with electrum at the point of setting the derivation path. I cannot find a good tutorial for the Trezor One
• There appears to be significant drawbacks to multisig with hardware wallets
• and technical challenges which my family may not be able to overcome in the event of my death.

Therefore the next best thing seems to be splitting my seed phrase up and giving 3-4 words to friends and family. This has the disadvantage that ALL the friends need to be contactable if I die in 10 years. They could collude to steal, but this is the same as multisig. I don't think it's reasonable to try and brute force 20 words of a 24 word seed phrase.

Am I missing something? Is there an easier, secure way to do this? Ideally I would like to multisig encrypt my entire seed phrase so that m of n trustees would be able to unlock the whole phrase, allowing a little redundancy.