Hi Bryan,
Just a quick comment about this part...
On the smaller issue, DOIs for publications, electronic or paper is a no-brainer. URLs were never designed to be permanent. URLs were designed to be reused and be flexible. With DOIs we can place the same paper in multiple digital or physical locations and reliably find copies.
URLs were also not designed to be particularly impermanent - they were simply designed to be used. Technically there's nothing about DOIs that makes them more permanent than URLs. It's the management strategy behind it that makes it a "safer" choice. Nothing prevents a similar strategy to be built on top of URLs.
By the way, there's a classic document by Tim Berners-Lee about the persistence of URIs: http://www.w3.org/Provider/Style/URI
The big truth there is that "URIs don't change: people change them".
Best Regards, -- Renato