Example:

User A (Power user) has used a few hundred credits and still has some hundred credits left, which will remain unused during one month.

User B (Power user) has used up all credits during the same month. Additional credits are required for the shared pool of credits so User B can continue working.

Instead, it would be nice to have an option to share all user-bound credits for the entire account.

This way, User B uses credits from User A (and possibly other non-active users) first before additional credits are required.