The US National Academies has recently published a study report titled “Cryptography and the Intelligence Community: The Future of Encryption” that focuses on the balance between encryption and decryption in the coming 10-20 years; it uses a scenario driven approach to analyze the landscape. The report, plus a highlights document, can be found here, along with some background on the project:
This work included consideration of the implications of quantum computing developments, but was scoped much more broadly.
There was a launch webinar for the report on September 13 (which I attended) that provided an excellent summary. This was recorded, and I expect that it should be available on the National Academies channel on Youtube in the near future.