Hey Belle, read about your new game and some thoughts if you choose to read it:
I am 100% on board for the female photographer deuteragonist. Woman wingman characters who are just as or more perverse than the male lead is always great, and you did a great job with fairy Belle.
I'd rather she's not playable though, but if you do insist on that, I'd do it carefully. I'd make it where if you make and name your character, you only name the male and not the female. And whenever you do play as the girl variant, I'd avoid making her the POV during sex, and her gameplay elements should only be to further the benefit of her and the male MC's plans. I'm not opposed to yuri sex, though MFF threesome is preferable to FF lesbian sex imo, I do like me some lady on lady either way. To that end, maybe a cut away so that you're no longer in control of the female character, and the male MC resumes POV as far as thoughts go, with him being able to watch the sex via hidden cams or the like?
They're photographers, so it's not out of their specialization and also would add some voyeur elements without going into "cuck" territory.
I'd also try to make the female character more overtly perverted. I love your perverse night visit scenes in LTTP for example, but Belle (fairy) I feel is underutilized there. She encourages MC which is great, but then stops. She doesn't comment on hot it is, ask the MC how he feels after cumming on his friend/co-worker/Evelyn and her relationship to MC, misses a chance for a fun little extra spice for the come down, and also Belle (fairy) doing something like licking a little of the cum off, or maybe sucks on the girl's tits while tit fuck, or helps BJ etc. Takes the perv accomplice to the next level when they don't only enable and encourage, but also equally partake.
Also, fantasy elements are totally welcome here. Even if it's not magic, you can still add it fantastical fetishes that requires suspension of disbelief. Magic or tech, new avenues to add extra spice is fun.
As far as the gameplay goes, I trust you'll come up with a fun and engaging system, and I think you know the time period to go between scenes now, so I have high hopes for what you concoct!