There are a few gaps with Q&A at the moment which I hope the product team addresses.
The first is the inability to associate metadata with the content as it's being ingested from a file or URL source. For example, if you upload a PDF, it would be useful to be able to provide key-value pairs which are automatically set as metadata on the resultant index from that source. At current, the process requires re-processing each item in the index and evaluating the source and then assigning metadata to the item. This functionality already exists on the API as long as you are starting from a QnADTO object rather than a file. A simple example is that you may want to associate a version identifier to a document that is ingested so that each Q&A entry has a version metadata tag associated.
The second is to "downgrade" a response. Currently, you can kind of "promote" a response by adding an alternate phrasing to respond to a broader set of vocabularies, but there's no way to make a Q&A item less relevant.
It's a great service, but still has room for growth.