I think we need Nimble website as a subdomain at nim-lang.org, making it more official and easier to find (nimble.nim-lang.org, or pkgs, packages?), but we need an eco-efficient way to build the pages for the packages, something without a backend, just static files.
I really like crates.io and pub.dev
For long-time storage of the packages, https://wasabi.com/pricing seems to be the most affordable option (no fees for egrees or API requests), but it has a minimum storage duration of 90 days, which in is not a problem in this case (because this should be like an archive of all open source packages). Check here https://wasabi.com/pricing/rcs-faq
For the static website we can use GitHub pages.