Please tell me your opinion about this!

You know, I've been thinking that's lots of people hates OC's because they're mary sue-ish and because the cliché plot. My soon- to-be fanfic is using lots of OC's since it's involved Pokemon, and I had no reason to put the anime characters in my fanfic because they're too childish... --well, except for some characters--. So, what do you think:

a.Using the old plot, which involved some ghory schene and some tragedy.With some characters badass background, or

                         b.Story about happy- go- lucky person who was unintentionally thrown into some kind of trouble, and loves to kill others with a smile in his/ her face.

For me, I love the first plot because it's involved in some kinds of things that I happen to like: tragedy. And for the second plot... to put it bluntly, i detest it. Because it's seems toooo forced out. I intended to use the first plot, but, please tell me your opinion, mister and mistress out there-- who knows a little about me in this net world-- is the idea is.... i don't know....cliché?

Anyway, please tell me your opinion -bows-