It's not the most polished thing but I find it quite fun, the variety in the characters is pretty interesting, still needs some balance tho, like Frank that is too damn slow or how only the first shots from Arcana come with those extra bullets that enlarge the range but after that she only shoots one blue ball, also skeletons with shields are really hard to kill.
Also at times I feel that the enemies are too small to shot at them correctly, have you thought about making the sprites bigger or reducing the space that the window show making them bigger in the process? I think it would help a lot.