The limitation on the movement could be interest but I think the gravity of the ship make it very hard to control (one missile upward is enough to make you go outside the map without time to catch it back). I think removing the gravity might make it more controllable, as the start of the games feel very hard (I didn't think I lasted more than a minute ... Also you mentioned collectibles, but I didn't so any, they might need to be more visible or different from the bullet.
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I actually thought the same, but the game becomes really passive and easy once there is no real motive to constantly shoot. The movement is kind of hard, but you actually get used to it really quickly! Thanks for the feedback. I will try to make a smoother introduction to the movement system. The collectibles were never planned and aren't present. It was mentioned that the objective in the story was to collect the parts of the ship to repair it. It may be a bit confusing in the description. Thanks! I will check it and fix it because it's truly misleading. Thank you so much for your feedback! It really helps a lot, and I will try to fix those errors after the jam!