Great additions to analytics!
The descriptions for Impressions and CTR confuse me. When I hover the mouse over the numbers in the dashboard it describes the timespan as "over the last week" and this article says "these only account for the last 2 weeks of data". To me these two seem contradictory.
To conduct the experiments you write about, it would be useful to have the uncertainty about the timespan the data is coming from reduced to calendar days.