This are real problems. With Redis I tried to mitigate some of this problems by providing an API that allows to retrieve the full state of the database just using available commands (without having to mess with the binary dump) including for instance reading the TTL of an expiring key. This allows to create scripts that are able to convert a full database into a CSV file, and restore back the CSV file into the DB, just using the net API.

Of course with key/value stores changing the structure of the database is harder compared to SQL databases, still designing a good data layout when building your application can help a lot to make it simple to add features to the application without to resort to scripts that rebuild the data in the key/value store.