All right. So. Sorry to leave this unanswered for like three weeks, but I had many thoughts to think on it! Thank you so much for your kind words about my blog; they mean a lot. So much, that I’ll destroy any pretense on Tumblr that I don’t read fan fiction, just for you. See what I do for you? :)
If anyone reads my blog at all, I think I’m pretty clearly biased toward Bones (“What?! No way!” says everyone, extremely sarcastically), so all these fics are Bones-centric. Sorry, that’s just what you’re going to get with me, but if you like my blog, chances are you have a soft spot for Bones as well.
I think you have already seen my post where I recommended, along with Equilibrium (#1 and still champion) and everything else PSW has written for TOS, some other gen TOS fics with Triumvirate feels, but here they are again for everyone else:
Watching the Watcher by stillwaters01 (and everything else by her as well): Great for Bones and Chapel, very medically detailed, hugely introspective.
Now, here are some more recommendations. This is by no means a comprehensive list of everything, only my thoughts at the current moment. One writer I was going to recommend deleted everything from AO3, alas. I might add on to it later, as I am absolutely sure I’ve forgotten things. To try to narrow this down, I’m going to try to steer clear of complete AUs. Mostly.
As is my wont, I am also largely going to recommend non-explicit or only briefly-explicit stuff, as I try to keep this blog on the PG side. I can’t remember all the details about everything, so check the tags before you decide to read, and make the decision that’s best for you.
Through a Mirror Darkly by GenuineSnoof is new; it’s a TOS/AOS crossover with Prime Spock and Bones (both Boneses, in different times) dealing with the Mirror, Mirror mind meld.
Other Gen stuff dealing with the Mirror, Mirror mind meld includes
ThatSassyCaptain writes some good stuff. Weight is a nice shortish character study off some canon episodes. The Dog Days Are Most Certainly Not Over features McCoy and giant doglike creatures. It’s very silly, and very enjoyable. Also, its sequel just happened to update yesterday for the first time in something like a year.
Incubation by Swiss Army Knife: Bones comes back from City on the Edge of Forever with smallpox and has to find a cure before he and everyone on the ship dies. Kirk is a jerk (okay, he’s still traumatized over Edith, but still). Spock is awesome. #ProtectHim
There are some very long works by Mary R. and Lynn S., which are older pieces but luckily online; try Unspoken Truths, which deals with The Enterprise Incident, and Betrayed (So. Much. Angst. So much. This one is really well-written, but also a really hard read.)
I haven’t read The Dorian Solution in a long time (it’s novel-length, as I remember), but it’s a very interesting premise: McCoy and Kirk accidentally partake in a planet’s ritual that allows one person to take on all the other person’s subsequent injuries. Guess who gets the short end of the stick on this one?)
Imperfections by Amatara: Canon expansion: episode/movie scene additions from The Man Trap to Generations. Fantastic characterizations and UGH MY HEART at that ending.
anonymous - The One Who Is Fire. Bones screws up a First Contact by being emotional. Gets whumped. Much action; much angst. Very Triumvirate. Just on this side of overwrought, but very satisfying and full of the feels.
Hollow Earth by beamirang (yes, another xenopolycythemia fic. Whatever. Everyone bands together to find a cure. Many feels.)
Aini_NuFire - Do No Harm: Short adventure with more Bones badassery
Now, various slash-type-things.
@klmeri is the reigning champion of McSpirk fic, is all-around stellar, and has even written a couple of stories based on my overly-detailed prompts: Grave or Gone and In Winter Snow Angels Sacrifice. My favourite, though, is Younger than Stars, which has a great, conspiracy-filled plot, and feels aplenty. But just read starting anywhere, honestly. Read them all.
I’ve already recommended @fireinmywoods’ sneaky, intricately-plotted and swoonworthy Palimpsest and other writing (McKirk), but for comprehensiveness’ sake, here she is as well (she’s also one of my favourite humans on Tumblr). Sometimes explicit.
Mardia - Fortunate Son: AU where Kirk wasn’t on Tarsus IV, but Bones was, as a 19-year-old doctor under the supervision of Dr. Philomena Boyce. The writing on this one is phenomenal, and the use of interwoven flashbacks with the present is stunning. Even explains why Kirk and McCoy’s eye colours switch in AOS. This is a must-read. One sex scene; can be skipped. McKirk.
laughter_now writes some great stuff. Absence Makes the Heart Grow Fonder is also a must-read. So much suspense, featuring Bones being a righteous self-sacrificing badass and awesome doctor. For sheer h/c angst and suspense with a happy ending and a description of drowning that literally made my lungs hurt in sympathy, go for Hold on Tight, I’ll Hold My Breath. McKirk.
PrairieDawn’s A Matter of Trust strung me out for the past 24 agonizing weeks, but just finished; lucky you. Spones AU with Kirk and McCoy on a medical ship captained by Pike. Joanna was injured in the Vengeance incident and has telepathy issues. Spock is a healer. Makes good use of the Operation: Annihilate! premise. Crisp, evocative, compelling writing.
JoulesMer does a bunch of effective McKirk stuff with Pike and Boyce. Try The Red Wheelbarrow, Xenopolycythemia, or S.O.S. Great for angst and feels and happiness, romance and self-sacrificing idiots. Some stuff is rather explicit.
Gammadolphin is another very entertaining writer who does a lot of McKirk/McSpirk and AUs. It’s all pretty worthwhile, even the incomplete ones. Try A Wish in the Dark for a Bulletproof Heart (similar premise to The Dorian Solution, actually). Also has a range of stuff from non-explicit to explicit.
…okay, I’m going to cut it here for my own sanity. Aren’t you sorry you asked?