I like the clean cascades UI, all utility apps should be made this way.
As long as we're forced to keep the frame open, I would like to see a more useful option for display info...I really have no use for seeing contact photos of the few custom contacts I've added to the app. I know the battery % has been done, but it is useful.
Also, it would be nice to have a "try it" button or selection for the different settings so you can hear the tone...I know you can preview the built-in tones you provided, but if I want to select my own, I can't preview it.