I've noticed a problem with this fandom. And, no, it's not Mary-Sues, because I know that that's what you're thinking. However, this problem could be a product of Mary-Sues.
What I've noticed is this fandom is unmatched in its hostility towards original characters. They're either ignored or burned at the stake by flamers. And it doesn't make any sense.
In a fandom where there is so much opportunity to create original characters, they are surprisingly scarce when one scrolls through the list of stories. In a camp as big as Camp Half-Blood, one must wonder why the only campers present are those that Rick has explicitly named (and not even all of those characters make the cut). The world of PJO is a large one, with enough space that Percy and Annabeth can take a vacation from being the centers of attention once in a while. There were quests and demigods before them, and there will be quests and demigods after them.
I know that Percy and Annabeth are our babies, and that we've spent 10(ish) books reading about their adventures (as a couple of the HoO books don't really focus on them). But we as a fandom have to realize that Percy and Annabeth were the original OCs. We didn't know them at first, but we grew to love them. And who are we to deny the new little daughter of Apollo who simply wants to be loved the same way that we love Percy and Annabeth. Who knows? Maybe you'll love her more.
Maybe I'm biased, as I'm wholeheartedly in love with writing OC-central stories despite their unpopularity. But I honestly feel like the fandom is missing out on a gold mine by shoving OCs into the darkest corners of the story list.
Maybe this is about Mary-Sues. This fandom hates them like no other. But we can't continue to let our fear of reading Mary-Sues stop us from giving OCs a fair chance. Actually, if we shake this ridiculous phobia of wasting five minutes of our time reading about a Mary-Sue, we can actually make them less of a problem.
You heard me.
Reading more stories with OCs and giving the authors advice will decrease the amount of Sues if the fandom, as those authors will learn how to write real characters. And then everyone wins! The author gets recognition and a chance to grow, and the readers get to read about a new and possibly fantastic character!
After all, we can't all be fanfiction writers forever. Most of us dream of moving on and eventually becoming published authors in our own right. But we can't write our own original stories with our own original characters if we don't practice. That's why I believe that OCs are so important, and who we should encourage them, not tear them and their authors to pieces.
Let me know how you feel about this, whether you agree with me or not.