Considering installing new skins is easy and well known, and the fact lazer has it's own new default skin, I don't think changing the default for the current client makes any sense.
I think you shouldn't remove for example the 300's because if your a beginner you maybe don't know how the score system works so it's useful to see how many points you get if your hitting the circle perfectly. You can change your skin after that. I think the defeault skin is just for beginners to see how the game works. But I would wish for tournaments like the OWC to have a different skin or an another version of the defeault skin.