Expand Premium Pass subscription features:

Assign a unique role on Discord server to Premium Pass owners to make subscription more appealing. Can be automated via Discord bot with access to parsed player active subscription data.

Additionally a "streak" system can be added to incentivise recurring subscription.
Example:

2nd month: 70 gems, 100 energy, 150 crates, 2nd level Discord role
3rd month: 120 gems, 150 energy, 220 crates, 3rd level Discord role
4th month: 170 gems, 200 energy, 300 crates, 5-star sticker pack, 4th level Discord role
etc.