Smart Contract is your best choice. You can program your last will and testament. Besides 12 word mnemonic and 24 word mnemonic for BIP39 and Electrum is your choice.
Electrum word mnemonic and BIP 39 word mnemonic may have differences but there is no such thing a single point of failure if you keep multiple copies of your mnemonic.
Hard copy your mnemonic into metal slugs. Keep it in high places covered by soil like a time capsule while you are hiking so that only you will know where it is.
Half of your crypto assets should be given to people you trust using multi signature escrow system they are the ones whom will remind you if you suffer from Temporary Global Amnesia. Besides TGA is but temporary. So don't worry. The TGA in movies are unrealistic.
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