Recently we had an defect with trainings that caused Cloudfront it to return a 403 error under specific circumstances, by default it returns some XML which is not user friendly and does not look professional.
Ideally this issue won't happen again but in the case that it does, it would be good to have a custom error page in place that has some graphics, a user friendly message and perhaps some contact information. It would go a long ways in making our platform look better even when there is a an error with our Cloudfront content.