Here are the things I asked for! Remix and dismantle at leisure.
ALPHA!JADE
I am not interested in her interactions with baby Jake or Alpha!John; I am very interested in the building of her technological empire (what does she make, who are her clients, how does she get started) and also in her interactions with the Condesce throughout her life (possible eventual horrible attempts at seduction, go; possible momentary horrible temptation, HELP). I was recently made aware that Alpha!Jade/Alpha!Rose has magnificent potential but Alpha!Jade/Inventing Stuff would more than suffice. Art note: I'd like to see her older than forty. Rifles and machinery a plus.
ARADIA
Points of interest: why and how is archaeology a thing on Alternia, what might her life have been like without the game (short...?), her telekinetic abilities and creative use thereof. I'm also really curious about what she's been up to in the dreambubbles. Gen is A+, but if you prefer writing or drawing romance then seeing her auspisticize angry ghosts (WITH HER WHIP perhaps) would be swell. I'm not interested in red romance but always up for lady kismesissitudes; I can't get isozyme's idea of Helmsman!Aradia♠Captain!Vriska out of my head, if that's a direction that interests you. It may be useful to know that Aradia♦Sollux is my OTP though obviously this is not the showcase for it. Art note: I am not going to make you draw even one robot. I like her best when she's smiling, victoriously or viciously.
NEPETA
Canon facts about Nepeta: big-game hunter and explorer, Derse dreamer, brews a mean cup of tea. Nepeta getting mixed up in adult Alternian politics in a non-Sburb AU could be really great, especially if she ended up arse over teakettle in some kind of position of power. If you are stuck for ideas, put Obstreperous Character X (VWISKERS?) in a fix and have her get them out of it. If you can sell me on her in a genuine kismesissitude with anyone, go for it (don't feel that you have to, though!). I am not interested in a focus on any of her other quadrants and romance is not necessary, just Nepeta running around being a bright-eyed little dork who could skin and gut you barehanded.
(Confession: I think Nepeta♠Vriska could be hilarious. Vriska thinks Nepeta's 8eneath her notice because come on she's like the size of an after-dinner mint. Nepeta thinks Vriska needs a comeowppance. Maybe they screw up each other's hunts! Suddenly Vriska is cut all to fuck by those claws and oh no, it was hot. I like it when a character is underestimated right up until the point they raise all hell.)
PM
Worldbuilding prompt: how does the mail system in the Incipisphere even work. Postal workers apparently can and do travel absolutely everywhere, so if you know me at all you saw my suggestion of Prospitian Spy PM coming like nine miles back. Unreliable Narrator PM would be fascinating, with or without this: she handles that sword awfully well for someone who never dreamt of such a thing. I don't exactly ship any of the Exiles so much as I just want them all to live in a garden and lie in hammocks holding hands and clinking gently, but if you are partial to PM/WQ and want to work this into the above, go right ahead. Art note: dogtier avenging angel PM is excellent, pre-or-post-canon PM happy in her work also excellent; canon-carapace, human, insect-alien, sleek mechanical, all conceivable versions of PM excellent.