I would suggest to reduce the bullet spread of the player bullets.
if you allow players who can better aim to kill more enemys in fewer time this would be good.
i like your backgrounds with the planets and so on, but you could really easy improve the quality of your sprites for enemys and playerships. hope you go on with that project. greetings from Aachen - Germany

Sounds good to me.

Thanks for the feedback,
The game isn't finished and a lot is going to change.
I made this game as a little project for school.

The reason I uploaded this game before it was finished is because I want the game to be influenced by other people.
So if someone wants another spaceship they get another space ship.
If they want another gamemode they get another game mode.

It might take some time to create what everyone wants but if it makes the people that play my games happy than I'm fine with it :)

Oh, and the double bullets key could be better if it was on the mouse, as it's kinda hard to move and shoot, especially with keyboard ghosting.

First things first, I find it kinda odd that this game was published 3 days later I published a game with very a similar concept. Did you make this game based on mine?

Anyway, I agree with amusudan, altough the UI seems to be a placeholder.

I don't know if I'm a bullet-hell god, but the game seemed to be way too easy, to the point where I purpousely killed myself to see the death screen.

The feedback is lacking, at least for me. It's kinda hard to tell when you level up, and not having any kind of sound effect at all didn't help. We may be in space, but I wanna hear some boom-booms when I kill something!

Are the ships' hitboxes rectangles? Because when I got to the point of bigger ships and storms of green bullets it was very noticeable.

I don't know how much it affected other people, but having the player off-centered (even when not on the edge of the room, which is quite small) wasn't the best thing for me.

Alright, first of all you should try making better enemy AI, and better movement in general, it's in space right? then why don't I keep floating in one direction? Also the square explosion particles look a little weird to me, and how the bullets are bigger then my own ship. Make the UI a little bigger, I only noticed that it even was there halfway through the game. Still the game is solid, but a game is never truly finished (atleast not for me ;)), so try adding more different enemies, add rockets that home in on their target, more levels, more special effects!