*laughs* Yeah, sounds true. I did a rant a little while ago on "sequel children," who are usually boys, and who usually look exactly like their father, have the same adventures as their father, and hate their father as some kind of "issue" to angst about. It's terrifying how many I could come up with on the spot.

That said, I generally try to keep OCs to a minimum in my own fics simply because I figure people want to read about the canon characters more than they do OCs. And as you said, imo it should be a rule of thumb to ask what an OC can do for a plot rather than how funny/awesome/cool they could be. At least that's how I try to go about it. On the flipside, an OC who is just created to make the canon characters look cooler/prettier/smarter or whatever is just as bad.