I have now started work on loading the data of test case results for a particular action, and once that is done, the report command will start yielding really useful data: i.e. it will actually tell you what happened during a particular execution of a test suite. The way I'm approaching the work these days is by building the skeleton code to implement the basic functionality first (which actually involves writing a lot of nasty code), with the goal of adding missing pieces later bit by bit.
For example, at this moment I'm only targeting text-based outputs with a limited set of data. However, when that is done, adding extra data or different formats will be relatively easy. Generating HTML dashboards (without going through XML, as was the case of atf-report!) is definitely highly prioritized.
By the way: I just realized it has already been one year since Kyua saw life. Wow, time flies. And only now we are approaching a point where killing the atf-run / atf-report pair is doable. I'm excited.