Simple 2-of-3 multisig hidden across different geographic locations I check regularly.
Each backup contains a paper copy of the seed, the HWW device (ColdCard Mk4), and the xPub quorum for all 3 keys. Backups are stored in waterproof, tamperproof bags and further enclosed in a plain manilla envelope.
It's tempting to do elaborate backup schemes the same way Voldemort hides his horcruxes, but simple is always best.