First of all, thanks for the plugin! I was looking for a simple review/rating plugin that actually uses rich snippet or microformat and came across Author hReview.
May I suggest few things that I think will be useful?
1) Option to show/hide review date and last modified date.
2) Ability to choose between author's full name or username to display in the review box. Right now it's showing username but I need it to display the full name.
3) Uniform structure for review details. Right now some are using 'span' tag and some are using 'dl'/'dd' tags. I'm not sure if this is required in order for rich snippet to work.
4) Option to change the button text. Right now it's fixed as 'More Details' and it would be nice if I can change it to 'Visit official site', etc.
Anyway, just my suggestions :-)