Thank you for raising a suggestion. But I feel sorry to say, at this point, their are no plans for any more enhancements in Custom Reports module. I am trying to provide all the options possible through Report builder module and this requirement can also be achieved using Report Builder module. I would build some sample gadgets using Report Builder module and share it through some medium and anyone can probably customize it based on their requirement. You can also build your own report and once you get familiarize with Report Builder, you can almost build any kind of report with it.
And definitely, I can support you building any reports with it. If your requirement is something useful for other users also, then you can even post it as a new requirement and I myself would build it and share it.