My suggestion is essentially just making it so you can purchase larger amounts of GB. Currently, the highest you can buy all at once is $100 (or 200 GB). It would be a lot more convenient if there were higher amounts you could purchase!

These are the amounts I'd personally add!
$200 (400 GB)
$300 (600 GB)
$400 (800 GB)
$500 (1k GB)

For those of us who were already going to purchase a large amount of GB, it's a lot easier to just make it all in one purchase!