In the main series Diamond dust is a variation of snow, so combining them makes sense. Both are outclassed, with diamond dust being outclassed by sunny and snow being outclassed by Hail. An additional improvement would be it activating the ice and fairy gems as currently it doesn’t activate either leading to it being worse. I think this would turn it into a good alternative to hail and sun, and I’d really like to actually use diamond dust as it looks quite nice.