Hey @Kris F! Thanks for your post.
I really like your idea of using this workflow as a way to vet what team members intend to use credits for. While you are correct that you can do this individually, there are actually a couple ways to manage access to paid AI credits in bulk.
The first way to do this is to use billing groups. A billing group admin can enable or disable paid credit access for members of their billing group. They do this from their billing group dashboard using the same Paid credit access enabled toggle as seen for individual members on the People dashboard. The second way is through bulk actions on the Admin dashboard. Go to Admin > People, select checkboxes for members, then use the bulk actions menu to enable or disable paid credit access.
You are right about having a default setting; and while I don’t have any info about that, I’d keep an eye out on our Release Notes page for major product news and updates.