I like it. The look and feel kinda reminds me of old games like Star Fox. But I have some suggestions. You could have put a starfield with particle effects that move backwards. That would make the ship seem like moving forward. And the shield should have an effect to show it's going off. And also there could be a dash like powerup where you just blast forward with great speed for some time without taking damage. And I don't think the game speeds up as we progress, does it? It should.