Great production value on this game! I think things like having an attractive title card and an intro cutscene actually go very far in terms of making the game feel polished. I was certainly impressed when I first started.
I think Biboo's hitbox is quite big. I found it very difficult to dodge things and instead relied mostly on hoping to hear as much as possible from the tea and coffee drops. Fortunately that seemed to work out as I was able to beat the game by taking and healing a lot. However, it does mean detract a bit from the game design when you can heal your way through fights. I tried pretty hard but always seemed to get hit by the bosses's attacks. But the relatively plentiful health drops meant i was able to make it through anyways.
I don't think I was quite a fan of the healing items changing your movement, as they made Biboo a bit too uncontrollable for me, which made it even harder to dodge attacks.
I tried both weapons. The heavy attack seems to be a clear favorite against smaller enemies, being able to take out groups with just one burst. But the light attack's range and safety made it better against the boss. I did get pretty tired of mashing the attack button at the end though. I think I would have personally preferred 2 attack buttons or swapping weapons so you could hold to fire rapidly but it worked well enough for me at the end.