I can't remember if you've said it before, but are there specific reasons behind Akari's team in oop? Typhlosion because that's her starter, but why slyveon and an alpha luxray? And is there a reason behind her starter choice? I think the way people choose the mc's team is interesting, and yours seems like it might have been planned out, given that you specified she only has three because she's a researcher more than a battler. P.s. I hope Rei keeps that porygon, it seems so eager, like it wants to be useful really badly! I liked that the reasoning behind its inclusion was because it's from the future and is used to humans instructing it in battle. I found that very nice world building and a clever solution to Rei's dilemma

oh this is a good question!! yes i have thought about it!! and actually this is sort of tangentially related to the other topic abt competency levels.

what i mean to say is like, akari is a modern trainer with modern trainer knowledge, but she's not, like... a pro. she's not choosing for strategy. in hisui she's really going through what a kid on their gym challenge goes through, in building up her first team and all, except akari also is, like you said, doing research more than battles, so she keeps her slots freed up for the pokemon she's researching.

and on that subject, luxray and sylveon actually are (or were, really, they're now official Permanent Team Members) long-term research subjects. both of them are intentionally ones you can pick up very early on, because that's the time when she would have been properly building up her team, and by the later areas she already had it set.

sylveon is here because eevee has these super funky evolution patterns, and laventon was like, ok, new idea, try to NOT evolve this one and let's see what happens. so she kept it on her team but avoided exposing it to anything like a stone that would trigger one of the known evolutions. and then it stayed with her team through the fieldlands and part of the mirelands questline (i haven't fully settled yet on where it evolved exactly, i mean it could have been anywhere really given how much grinding the game lets you do purely via research, but i think it was maybe the fortunes battle?) and then wow! surprise fairy type!

and laventon went WHAT IS THAT, because sylveon are exceptionally rare in the wild and really require a trainer bond to appear. although pla merged the requirements mechanically, psychologically it's a different sort of "friendship" to the kind that they form with another pokemon or a more hands-off partner like the clan leaders.* so she kept it to study how it performed in battle. and also because she loves it lots and lots. (*out of universe, i think sylveon is also apt because it contrasts with the teams of eeveelutions the leaders have in their later fights, notably neither of which include a sylveon.)

luxray, otoh—and here i was sort of kicking myself for a while for not making it kricketune, because that would have been such a nice canon plotline tie-in, but kricketune's pla moveset is also actual ass so it's probably a good thing i didn't—but luxray is the first alpha akari ever caught. and, quite possibly, the first alpha anyone had ever managed to tame at that point. (er. anyone in the galaxy team. they did not know about ingo then.) she caught it as that luxio you find on the way to floaro gardens, by being very sneaky and also very lucky—she went after it half because it was an alpha and they wanted an alpha specimen, and also in hopes of helping zisu out, bc she was worried about having that alpha so close to jubilife but couldn't take it on herself. (cyllene was mad at akari for A While for taking that risk, altho very quietly.)

then akari kept luxio because lav wanted to see more of how the alpha phenomenon affects pokemon beyond augmenting the physical size and strength, and what of those effects persist after the red-eye frenzy dissipates, for example, they know moves they don't learn in the wild! what's up with that?? and alphas are very likely to respect and like the people who catch them, and irida sort of hints at why in ch11- being frenzied is an awful, terrifying experience, and they know that the person who caught or battled them into submission was the reason they're free from it. if you let a pokemon go after defrenzying it, it'll forget fairly quickly, but since akari kept luxio on her team, it instead formed a trainer bond with her. and it was a beast when she caught it, and that hasn't really changed, it's her strongest physical attacker. it evolved first out of the group, i think.

as for cyndaquil... honestly, out of universe, this was mostly process of elimination. cyllene already has oshawott for the swordsmanship thing, and lav has rowlet on a vibes basis. in universe, i think cyllene also picked up oshawott as a partner before akari got there, since it's now a dewott and evolution doesn't happen in a day (unless you are a protagonist going apeshit on dex tasks, but this is not really canon progression, it's slower than that in reality.)

akari's real reason for picking cyndaquil specifically, tho, was probably mostly empathy, bc unevolved cynadquil are lil balls of needles and shyness, and she was sort of like, y'know i'm also very scared of The World and want to curl in a ball and shoot flames at people. i think laventon offered her a partner more as insurance for her first ever outing than imagining it would be her permanent forever partner, but for the aforementioned reasons they bonded super fast and now are inseparable.

cyndaquil's evolutions are another thing i haven't 100% settled on, but i think they happened at important canon moments—the fight with kleavor for the first, and then... i'm not sure about the second. it could've been lilligant, i suppose, but i could also see it happening at some later point to space them out a bit more. (i could even see it happening during the ingo fight, lmao, altho probably more for some future fic than as going canon.)

...oh god that got long. oops. uh. yeah you could say i've Thought About It. re: the rest of your ask lol, yeah i also really love porygon!! i'm not gonna ramble on bc this post is too long already and you basically hit everything i would say already, but YEAH i think their inclusion/existence in pla is really fascinating and they make for fun characters. so. yes! porygon is gonna be a going thing!