I think it would be cool to see what keys have been pressed the most, i play alot of WSAD-keyboard games, and id like to see separately all keys that have been pressed. And an image from keyboard with blue yellow and red colors for example, indicating times that key has been pressed or something like that would be cool. 
Not really a NEEDED feature, but id like it 
You can use that in conjunction with the Key Frequencies.
I think you NEED to have the key frequencies enabled to do that - that chart just translates the chart into a color-coded keyboard image for you.