TL;DR: Mukurozi's hitbox is less visually clear than the other two's (Make her scarf glow a brighter red like the Saba's hairpin in NEHONOBASA), and Mission mode is a little repetitive, but the nre characters are a blast to play, and Scenario mode is a fun way to learn them. Putting the base game in there as well is a neat touch, and a great challenge as the new characters. I also like the art on the thumbnail and in the cutscenes.
Perhaps you could also make the hitbox visible again for clarity reasons. Sure, there was a visual bug in the original where Hakuto's hitbox would sometimes cover one of her eyes, but that's funny, and you could explain it as Hakuto winking at the player or something. The visible hitbox also made the visual pollution of the foreground in 3-1 much less overbearing in the original.
Overall, I love it! Keep up the good work, nizakashii.