So I don’t know if these two series have reached this neck of the woods. If not, let me introduce you to two stories I keep coming back to. They are both really long so I don’t recommend starting on them until you have a couple of days to spare. Don’t say I didn’t warn you :)

Harry Potter and the Methods of Rationality by LessWrong aka Eliezar Yudkowsky
TVTropes page

A 500 000 word, finished fanfiction about Harry Potter which aims to wrap up the main arc in Harry’s first year. Also contains more Crowning Moments of Funny than you can shake a stick at. Basically, Petunia Evans married a scientist rather than Vernon Dursley, and Harry grew up with loving parents and more books than he can count. And is also basically a genius. Featuring a sharp and kind of creepy Professor Quirrel as Harry’s mentor who gets students to form armies and battle each other non-lethally to teach them Defense Against The Dark Arts, Draco and Hermione as Harry’s best friends, and several author filibusters that are still entertaining. Oh, and complex plots ahoy! Epilogue updates on Pi Day 2016, which has either already been or is about to be. There is a dearth of positive female characters in this work, and as such has been accused of anti-feminism, but I argue that the author didn’t have a lot to work from anyway. Is. Epic.

Luminosity (Rational Twilight #1) by Alicorn, aka Hannah Blume
TVTropes page

What if Bella actually a) gave a crap about people, and b) was methodically dedicated to getting the best out of life. Starts off normal and begins to deviate really rather rapidly, quite quickly. More of a story than an exercise in rationality.

Radiance (Rational Twilight #2) (see the above link and scroll down a little)

A sequel narrated by Bella and Edward’s daughter, Elspeth (in book 1, they comment that there is just no way to smush the names Renee and Esme together without sounding like some kind of Pokemon). Featuring way less creepy imprinting, Volturi, and Renesmee’s power is turned into complete and utter awesome.

Both posters hail from this forum, LessWrong

I highly recommend both. They are very well thought out, and are incredibly readable, and most importantly, finished!! Have you guys read either? I want to fan about them with someone!!

Edit: Bonus rational fiction: My Little Pony: Friendship is Optimal

half the time Harry’s “genius” was just tiny dei ex machinae jumping in to give him just the right flash of insight at the right moment

examples?

Honestly, I know what you mean about the language use and condescension etc. I should have mentioned that—but once I learned to ignore it, I felt really swept away on a great story. I’d really love to know what you think about Luminosity, it’s far less condescending and pretentious.