Oh gosh… the answer to that wouldn’t fit in the limited space given here.
I love almost everything by NairobiWonders. If i listed every story I loved by her you’d never get through it all. I suggest just going to her archive and reading up: http://archiveofourown.org/users/NairobiWonders/pseuds/NairobiWonders
I also really like a lot of the stuff Time Converges writes: http://archiveofourown.org/users/time_converges/pseuds/time_converges
…and language escapes: http://archiveofourown.org/users/language_escapes/pseuds/language_escapes
Language escapes writes really well. Her story “for the sane mad and bravest of monsters” isn’t really what I would normally read because it’s not really even Joanlock but i still loved it so much. I loved the background on Sherlock. Her other story, “the lopsided symmetry of sin and virtue’ is much more popular and has a more fun concept of joan and sherlock pretending to be married for a case… so it’s great. But i think this is actually her stronger fic.
Recently I’ve been crushing on these incredibly well-written babyfics by Vahkhiin: https://www.fanfiction.net/u/648690/Vahkhiin
I normally would stay away from this genre in this fandom… i honestly just didn’t think anyone could write sherlock convincingly as a father. But i have to say these are great. I think they may be some of my fav stories:
In the Quiet Hours of the Night: https://www.fanfiction.net/s/9372477/1/In-The-Quiet-Hours-of-The-Night
Walking Home: https://www.fanfiction.net/s/9555614/1/Walking-Home
There are so many great little stories out there. Here are just a few more:
A is for…: https://www.fanfiction.net/s/9208390/1/A-is-for
Miles to Go: https://www.fanfiction.net/s/9922992/1/Miles-to-Go
I could go on forever. I’m posting this publicly so maybe some other joanlockers who have their own favorites can add to it.
I second the recommendation of NairobiWonders. No one can write Joanlock like NairobiWonders!