Please note, I'm going to provide two responses to this thread. The first one is official and the second is personal.
Admin response:
Story Comments are provided for at all stages of a story's posting. Reviews are provided for when a story is complete. Would it be nice for a review to be in depth? Hell yes. the "Was this useful?" is a subtle way to encourage that. I find reviews that are more detailed of pluses and minuses more helpful and mark them accordingly. As an author though, as covered elsewhere, a star rating and I liked it is still better than nothing. Beta Readers and Editors should be providing these critical reviews to the author... or they aren't really a beta reader or an editor.
My personal response:
In the fifteen years of running this site, I have tried pretty much everything to get more reader engagement with the authors. This has built the community well enough, but we still lack much in the way of comments and reviews. I've said this in various places... but only about 2% of the site traffic can even do so. Most people reading on Gay Authors are not members at all.
Forcing a format does not work. The most it will do is stop people from reviewing at all. If you want more than you are getting, then engage your readers. Ask them in the chapter end note or in the story note to give a detailed response. Tell them you want to know what works and what doesn't. If they like what they are reading enough, they just might do as you ask. Some people certainly aren't going to say something if they are afraid they are going to melt a snowflake.
@William King In the interest in providing feedback that you crave, I'm going to say this: you attract more flies with honey than with vinegar.
Your suggestion that we promote a story a month... we already do this and the amount of effort that goes into it doesn't leave much room for more without more active volunteers. It is still linked on the bottom of the main forum page and in ads running on the site: