We've yet to see any significant progress made on adding value to players willing to give money for the LTS/Subscriber benefits.
I have one suggestion, and that would be to grant an earned dilithium bonus of 25% for content completed while actively subscribed to the game or with a LTS account.
This would not allow a Sub/LTS to earn more refined dilithium per day on any one character, the refined Dilithium cap would still be 8k.
The difference is that as a subscriber you would be getting a perk of time convenience for your subscription dollars.
Player A is a current subscriber.
They complete Mission 1, which normally grants 1000 dilithium.
As a subscriber, they earn a bonus of 25% extra dilithium - so this mission grants them 1,250 dilithium.
This means the subscriber would need to do less content to earn their daily cap of 8,000 dilithium, freeing them to enjoy other content faster - thus it is a time convenience for paid support to the game.
Player A decides to cancel their subscription for a time, during this unsubscribed period they lose the +25% earned dilithium bonus on mission content an would receive 1,000 dilithium from completing Mission 1 above.