Thank you for playing the game and for the feedback.
Apart from your first observation, I agree and we will implement all the others, but as for the first one the difficulty is a part of the challenge: the bullet fires away from the player when you release the mouse.
That said, when people play the game, I notice that they don't use the "refire" system, so it may be TOO difficult or complex, so I should enhance it or change it, but I don't know what I could do.
Anyway, the changes won't be made soon, because this year I am studying to sit the exams to enter university. I will make them though. Again thanks for zplaying!!!