Billing Dashboard
The new billing portal has demonstrated enhancements but I still feel it's lacking in functionality that most business owners would want to see more of.
trend management, especially with a contact center instance, I find it difficult to see the invoices over time and compare them month to month. Why isn't there a dashboard that can demonstrate this graphically, leveraging the filters you have there now as toggles?
Export/Download, currently this exists on an invoice by invoice basis which is fine; however, I imagine many of us would like the ability to export the billing list as its represented in the portal. It gives us another option to view the data in aggregate, over time, and incorporate in other styles of media to internal stakeholders. Either graphically and/or in an excel, PDF, CSV format should be available to easily port them to charted views for executive leadership.
Once you're this far, other features become apparent as organic adds: scheduled emails, threshold notifications (go over x $$ send notification) and finally, some time of note regarding milestone and plan adjustments. When the changes came with how billing was demonstrated with overages, future vs. past, having a way to mark that in the portal or flag the invoice in which that started seems appropriate.