Right now it's ordered by season, but since my new favorite genre is "pair a new season with an old season!" that's kind of a pain. Other than rid myself of that, I guess I'll just try to shamelessly emulate glorious_spoon's masterlist, because hers is the only one I've actually used (and use fairly regularly! as everyone should!). Though admittedly I'm not sure how much of that is her skill with masterlists--though it is prodigious--and how much of that is her masterful skill with summaries and, you know, writing. :P
The shortlist of categories I am considering:
fics where Sam eats, or fails to eat an just ruminates on, strange confections
endless numbers of 5x22 AUs and codas
a weird number of Mystery Spot AUs and codas
fics about minor/unnamed/throwaway characters; ladies, mostly
creepy experimental prose
psychologically or emotionally compromised experimental prose
fics that basically just fridge Dean and roll from there
Dean H/C I am proud of
embarrassing Dean H/C no one in the world would be proud of
Dean/suicidal ideation, which is so populous it gets its own separate category
fics I have gotten in trouble for writing (sorry, Dean fandom)
fics the world really, really didn't need
I mean, sure, it SOUNDS like I'm being facetious, but those actually are pretty accurate categories. The only other things I might add are "S9 tags" and "Meg/everyone, usually Lisa." And I figure this would be a great opportunity to redact things that are not worth listing, thank the lord.
But are these categories useful to people who aren't me? That's the question. Actually, the question is, does it matter? Do people even use masterlists?