owlmoose asked, Although I'm mostly familiar with your fanfiction, I know you have written original fiction as well. I'd enjoy thoughts on how they are the same, how they are different, what you have learned from one that you can apply to the other, and anything else on this topic you'd like to discuss.
First of all, thank you, KJ, for such a fantastic question, and second of all, I'm so sorry this answer has taken me forever to get to posting. I've seriously been jotting down notes on it all month but then life. *throws up hands*
So, at this point in my writing career (what a funny thing to think of, since none of my original fiction is published),
my AO3 stats page tells me I've written 319,645 words of fanfic. It is about 275K-300K short, given unpublished things scattered around assorted and various Scrivener projects. We'll call it a grand total of 600,000 words of fanfic, give or take some statistical massage. I couldn't tell you how many words I put into long-abandoned original fiction, but given my certainty of the projects I can think of off the top of my head (i.e. the five novels in various stages of completion) and my knowledge of about how many pages I would tend to get into a given project before abandoning it in my teen years, I think I'm probably sitting at solidly 500K.
A fairly even split! More even than I had expected, actually.
When it comes to similarities and differences, I think there's a lot of duality - coins with different sides but the same value. I find that when I write fanfic and origfic, it tends to be thematically similar but structurally different, with one important caveat on the latter.
Thematically, I like stories about redemption and struggling against a system designed to break you. I like big sweeping fantasy epics where you save the world. I like very particular character archetypes that won't surprise anyone who's been around here for more than a few months (competent and reserved women; rogues with a heart of gold; broken knights; snarky characters of all descriptions; the quiet ones with the infinite reserve of strength). We've all got our tropes. Likewise, the kind of stories I want to tell have themes strikingly similar in both, like picking yourself back up when the world has done its best to break you. Another thing I love that I've mentioned before is the kind of loyalty and fealty that makes you walk into hell with eyes wide open and head held high, because there was no other choice. I like broken people trying to find a way to keep from cutting themselves on each other's edges. I like schemes and layers, even if I find them really frustrating to put together and keep straight.
Structurally, well.
Have a look at my tag cloud, and you'll see (besides the fact that I'm perhaps overly prescriptive and persnickety about my tagging) that my 1k-3k fics outnumber even my drabbles. (On a related note: Drabbles are hard, yo. And the prescriptive and persnickety linguistic martinet who lives in my head will never not be excessively annoyed by people who call a 3k-word fic a "drabble." I realize I've long since lost this battle, but I shall wave my flag fiercely nonetheless.)
I largely write short fics, with a few outliers (that'd be the 5 fics tagged as "length: epic" which I think I decided meant anything over 10K.) In original fiction, though, I'm not very keen on short story ideas. I have a small handful of them, but they mostly sit around waiting for me to stop being starry-eyed over novels. I think it's because I don't always know the characters in my short story ideas, and I don't want to spend the 10K to get to know them only to scrap that 10K and write another 5K to make the actual story happen. It doesn't seem like a good ROI, to put it in business terms. Likely I would work better by writing hidden moments and off-screen events - in other words, fanfic - of my longer works, but I've not gotten around to doing so. Yet, at the same time (here's that caveat I mentioned before about structural differences), I find that the length of a chapter is usually about 2000 words.* The 1500-2500 range seems to be about what it takes me to make a complete fictional thought.
* The chapters in Every Light are 6K long. Don't look at me like that. That fucking beast breaks all my rules.
There are three major things I've learned from fanfic that I try to apply to original fiction.
Characterization - I don't just mean characters having consistent traits. There's a thing fandom does, that i see only rarely (if at all) in published fiction, which is that type of third-person perspective so closely written it's nearly first-person. It's not just the propinquity to emotions, though; it's also the way given characters will see and filter various things when they look around a room. If I write Celes, she'll notice the placement of furniture and how it would affect her mobility, not any details of its beauty or construction. Edgar or Setzer, looking at the same room, would comment on the quality of the pieces, or recognize the work of a well-known crafter. Relm would observe how the arrangement of the furniture creates (or doesn't) impressions and artistic value, and how the colours interact. Everybody's looking at the same room, but they all see it quite differently. It's also the tone of the text, where Celes is brisk and no-nonsense and Edgar is layering multiple entendres onto everything. I love doing that in original fiction because it makes me think really hard about how a character would see the thing in question, and how they would react to it.
Worldbuilding - I don't know about you, but my genres of choice are romance (which mostly isn't relevant to this point) and fantasy. But the fantasy I grew up on, that I read in my most formative years, was rather as-you-know-Bob about its worldbuilding. Fanfic taught me how incredibly effective one sentence can be in conveying what I might have spent an entire paragraph pedantically explaining. Sure, I probably have to write the pedantic explanations myself so I know what the hell I'm doing, but getting them into the text? no thanks.
Sex Scenes as Character Development - true fact: NaNoWriMo 2013 saw over 5,000 words of fiction written that will never be published in the novel. They were pure smut. They don't belong in the novel because they're gratuitous, but they were important to write. One, because it was clearly the track my brain was on at the time and it was easier to just get the words than fight it; two, because it taught me an awful lot about each of the characters in the scenes. The finished product will almost certainly have such scenes in it, but they'll be doing double duty. Not just titillating material (though if I'm doing my job right, they'll be that too), but also something you didn't know about the characters before. Properly, this is rather a subset of the characterization point above - every scene should be revealing more about the character - but since fandom was the first place I saw sex used to convey more than "happy endings all around," and that was pretty effective on me, I thought it deserved its own point.
Interestingly, I think fandom has created a weakness in my original fiction, and that is creating characters. I find if I sit down and do those questionnaire thingies I just hate everything because no I actually do not care what her favourite food is, but I also can't discover more about the character as I go along the way I might in fandom. In the trilogy I've been writing the last few nanos, at the end of three books, I have a pretty good idea of major character traits for the primary dozen characters or so, but it took me three novels to get there and now I have to rewrite them all. (for reasons largely unrelated to that.) Maybe it's not that I have a problem with characterization, per se; I just find it harder to get started from nothing. Most of my origfic worlds have started with a setting that I then dropped people into, not people whom I then built a story around. The trilogy was an interesting balance between the two. (I have a similar weakness with setting, but that's more that I'm never sure how much description is too much so I cut it all in order to maintain flow and then my characters are basically in empty rooms. Oops.)
I was going to say that perhaps I am too used to playing with someone else's toys to create my own characters well, but in retrospect I don't actually think that's the problem. I have a consistent problem with being unable to judge my own quality of writing; sometimes things I think are awful and stupid turn out to be the first readers' favourites, and I know for a fact I am extremely, extremely hard on myself all the time about everything. So perhaps I judge myself too harshly.
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