Key point is that the cloud provider version should not be your "main" version, it should be used for backup only. If it's not on your physical computer that you have direct access to, it's not -your- data anymore.

> Local hard drive + a cloud provider

This has been my general strategy for personal data. I have also been trying to figure out if there was a reasonable way to get long-term very-cold storage (e.g. backups of family pictures). Something that would last decades just sitting in a fire-box somewhere (reasonable temps, no moisture). Been considering https://en.wikipedia.org/wiki/M-DISC, but interested to know if anyone has other ideas...

Don't quote me on this, but Bluray is apparently supposed to be long-term stable. I haven't explored the claim.

I actually use three local hard drives in rotation plus a cloud provider to hopefully cover the "building catches on fire and I don't even have time grab a drive" scenario.

Maybe a second cloud provider would also be good. I'm going to think about this.