Every one of us will have a different response and that is part of the strength of this site, that there are stories for every taste. For me, 'Forever' by Jack Schaefer is a top one, as well as 'Drummer Boy'. As much as I love sci-fi and fantasy, I tried very hard to get into D'Artagnon's writing. Don't get me wrong, sir, you are an incredibly gifted writer but I found after awhile, I preferred older characters as main characters. But I am glad you are there for our younger readers, who need positive role models and good things in their lives. And although I think the RU universe is a good idea, I found that reading about the same events, even written in different stories perspective, a bit tedious after awhile.
I want to read about characters who develop during a story and grow in love and character. I admit I am a romantic at heart and love happy endings. Those stories making me come to care about the main characters are the best. Any genre which gives me all that, I will read. To sum up: characters who make me care about them and want to keep reading, good dialogue, good plot and heartwarming moments.
I have not yet read all authors here either, so ask this question next year and although my main points will be the same, I bet I will have added new favorites to the list. Again, a strength of this site is its diversity.