Could we get a vocab coverage just like we have for the characters? Maybe turn them horizontal and put them under the other left-side dashboard containers? Maybe something like this beautifully rendered example from the masterpiece software MS Paint?
And additionally, could each of those little donut charts or containers be clickable to take you to a filtered view of the characters or vocab? Already filtered to whatever the level and SRS stage are that match the number in the container? I know I can use the top nav to go there and filter for it myself, and it would be a nice little convenient quality of life feature if the tiles down there were clickable.