I think it looks like she's doing a fine job.
For what it's worth, Synthesia 11 will be dramatically improving the quality of the sheet music display. So, if you wanted to lean more heavily on traditional notation while still using the other features (like melody practice and progress tracking), that will be possible.
In the meantime, you can bind the Settings -> Shortcuts -> "Toggle All Notes Hidden" shortcut to something like a piano key temporarily, start a song, hide the falling notes, and then unbind that shortcut. That will leave only the sheet music and keyboard. (Synthesia 11 will be promoting this option right to the play screen where you'll be able to independently toggle the falling notes the same way you can the sheet music today.)