Adding Limits to Custom Report Endpoints

We are currently researching a reasonable limit to the number of fields that can be requested in a single custom report. 90% of uses of the Request Custom Report endpoint request 30 or less fields. However there are some requests that attempt to get 1,000 or more fields in a single request. We will soon (within days) be implementing a limit of 400 fields on a single custom report request. We may lower that number further, but we don't anticipate going lower than 100. We will continue communicating about this as we find out more.