Always glad to hear your perspective on this. I am working on my own archival system for href.cool - I’ve already lost thewoodcutter.com and humdrum.life. (Been going for one year.)
My approach right now is to verify all of the links weekly by comparing last week’s title tag on that page to this week’s title tag. I’ve had to tweak this a bit - for PDF links or for pages that have dynamically generated titles - I can opt to use ‘content-length’ header or a meta tag. (Of course, the old title can be spoofed, so I’m going to improve my algorithm over time.)
I wish I had a way of seeding sites with you. I imagine we have some crossover on interests and would also love to contribute bandwidth - as would some of your other readers I’m sure.