It would be nice to be able to have a coloured border around the Key Image thumbnails. This would allow you to quickly notate and identify certain plays or good/bad things to find them in the timeline more easily after reviewing a video.
The Comment Box could have a colour selector which would allow you to quickly change the colour of the border while initially breaking down and notating a video. Custom colours would be ideal, but even 10 basic colours would be helpful. e.g. Red for bad play, green for good play, yellow for goals, blue for good breakout plays, orange for good defensive plays, etc are all things I could quickly use to identify moments in a video.