Hello Matt,
We are working on including new statistics, it is one of the items in our backlog.
Having said this, the statistics will never include notions regarding detection rates per brand, VirusTotal should not be used for antivirus comparatives, the reasons for this are stated in our FAQ:
Moreover, VirusTotal's philosophy is not to disrupt the antivirus industry but rather help them to improve their solutions. To this extent, we do produce some statistics like the ones you mention but they are only available to the antivirus vendors themselves, so that they can study their performance and improve their products.
We really appreciate your feedback and look forward to new suggestions.
Thank you very much.
Emi.