So i have M4 viking now and i have M4 Viking XT What will happen i will get my crystals spend on mu's back?

right now there is kits of 10 1 and 50 but if you want to buy 9 gold or 49 you have to buy 1 gold 9 times or 10 gold 4 time + 1 gold 9 times........so my idea is to give us the option to pick the amount of golds we want cuz when you buy 10 golds in a row you get block from buying and its bit annoying