I don't think myself to be eligible to suggest something at this reputation level. But, I found this helpful if it can be implemented.
I kindly request you to correct me if I am wrong with this suggestion.
My suggestion is:
To ToolTip the number of questions & answers the user has asked/answered while hovering the userName.
The reputation is shown on howering the Username of the Comment. And the Accept Rate is shown while hovering the Accept Rate. I have also seen this question. But, this is for the accept rate. However, it shows the number of Answers as well, but still I think it would be better to display the question-answer count as well.
I don't know if this is proper suggestion or not. I welcome your view with this suggestion.