Characters you would like to see again

[Aster-143]

Yumemi Okazaki for me, PC98 is underrated in general and she has a amazing theme and design (at least in my opinion)

[nAd]

even though it was already mentioned that ZUN has no plans of ever touching PC98 again, I'm still secretly hoping Elly finds some way to make it back in, her design is lovely and the scythe has good danmaku potential

realistically though, I just hope he continues to use the more recent characters from th19 and 18, at least for a bit longer

(also seconding Rika cuz she's fun)

[NovaDelta]

Serious answer? Mima. (Though that's probably too stereotypical)
I think the nearly 30 year old lore with her character could be built upon with the lore created over the decades.
I feel like her becoming more bitter over the years and finally enacting a scheme she's had in play for years to try to finally defeat Reimu or destroy Gensokyo or what have you might work...

might...

I think established by her ending in Mystic Square though,

Spoiler:

she's probably just become a sweet old woman (ghost) who's settled down and isn't as much of a vengeful spirit anymore. My headcanon is that nowadays, she is the retired mother to the now independent Marisa and respects Marisa and Reimu's friendship enough to not torment the miko.

Though another option, Demon #2 from Reimu's Mystic Square ending.
Looks cute, one of the few demons in the game that looks kinda like a demon (mostly just having the horns, being a demon trait) instead of a human that's called a demon.

And Yuki and Mai, that would be cool

While not an independent character per say, I do wanna see Reimu's Shuusou Gyoku design brought back. Colder season clothes, dual gohei, sorta a bridge design between the two
(Plus, her and Marisa's portraits gave us a glimpse into what the art of Mystic Square might've looked like if it weren't limited by the PC-98