I use openSUSE because I want to see the license used with a package before installing it, and I can do that by using YaST. Also, it seems that version numbers are used consistently which enables elegant downgrading (I found that the pacman system is probably capable of supporting this too, but the operating system(s) that use it don’t seem to use version numbers consistently and I’ve had a bad experience with downgrading in the past). I reviewed packaging systems other than rpm but it seemed that rpm while used with openSUSE was the most robust.
I also like having a bootable image with a streamlined installation process that is clearly supported by the operating system maintainers: I was tired of worrying about whether I set up LUKS correctly while setting up Arch Linux, and just having a checkbox for “encrypt the disk” makes me a lot calmer. Knowing that I can use a guided process if I want to reinstall the operating system also gives me some peace of mind.
It’s also nice to get practice with an operating system that is more similar to “enterprise” Linux distributions: it’s probably useful to get practice managing my personal computer(s) and at the same time get knowledge that is probably re-usable while interacting with Red Hat Enterprise Linux or SUSE Linux Enterprise itself. However, this was not a primary consideration for choosing an operating system for myself.
Luckily, my choice can currently also get some support from https://www.privacyguides.org/en/desktop/
I also like NixOS, but it doesn’t seem to use secure boot by default, and I’d prefer to have that handled without needing input from me, so I only use it when that feature isn’t available at all.
My opinions are likely to be in accord with information found at https://www.privacyguides.org/en/desktop/ and https://www.privacyguides.org/en/android/distributions/
As an alternative to making decisions without direct assistance, you might benefit from contracting with another person to make decisions based on requirements you describe (essentially getting a chief information officer (CIO) for yourself). The main reason I’m suggesting this is that having more people involved will make it more likely that someone will know about established best practices relevant to your situation or that someone will have experience with a problem that is similar to the one you’re dealing with. Additional reasons I could provide for this would be similar to the reasons people give to discourage someone from handling court appearances without a lawyer or doing surgery on themselves. You might be able to use https://ryf.fsf.org/categories/laptops to find information about how to contact people about your computing needs. Alternatively, you could visit a store (for example, one operated by Walmart).