I played your game yesterday... it's VERY good!
I really like how everything move smoothly, sprites collide and interact, and the main chara... she's so ADORABLE! Very good design and animations.
The difficulty level is good enough to me, after a while you understand the power of adding sword combo to hit combo. And the Spica kick.
Really good.
The only things I will change are silly stuff, so you understand how much I like the progress so far:
1- the navi had to be on another "level" than the capsule? Can you please move her just on the ther side of the room? More quick. And avoid the ranting on weather EACH time

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2- parallax. You added parallax elements to backgrounds. Did you plan to add more? Actually stages are a little empty.
3- the doki doki date is messed up, but probably you already know.
4- more waves of regular enemies before the boss.
Nothing else. So far the game appear good to me. MAYBE this will be the very first patronage I will do (you seems also serious about releases).