Totally agree! At Qri (https://qri.io) we're working on many of these problems together - hosting, formatting (interoperability), provenance and sync. It's an open source project - we'd love to have your feedback as we design it!
For example, someone else mentioned engima.com. I would have no idea that is related to data sources / sets unless I knew what it was.
Certainly wish you the best of luck though and will keep an eye on Qri! Cool project!
A web interface would be nice so that I don't have to install a tool to browse the content. Going to give it a shot non-theless.
You would be doing us a huge solid, working through these use cases irl is beyond helpful.