I wouldn't mind this if it was something that can be turned on and off. Also, instead of having a different pictures for late/early, I think the hit bursts should simply change colours depending on how late/early they were pressed. So for example, the user can select any five colours they want for the following judgements: very early, early, on time, late, and very late.
If the user picks yellow/green/blue/orange/purple respectively for example, the hit bursts (including 300s) will be solid blue when perfectly on time, between blue and orange when a little late and between blue and green when a little early. Solid yellow/purple when the object is hit as early/late as possible, and otherwise somewhere in between yellow/green and orange/purple. This would allow (with some visual training) the player to receive feedback on how early/late they are without needing to make any changes to skin elements and without having to look at the bar on the bottom, while also allowing players to define their own colours which they are comfortable with.
If the user picks yellow/green/blue/orange/purple respectively for example, the hit bursts (including 300s) will be solid blue when perfectly on time, between blue and orange when a little late and between blue and green when a little early. Solid yellow/purple when the object is hit as early/late as possible, and otherwise somewhere in between yellow/green and orange/purple. This would allow (with some visual training) the player to receive feedback on how early/late they are without needing to make any changes to skin elements and without having to look at the bar on the bottom, while also allowing players to define their own colours which they are comfortable with.