I like the concept. As you said, the game was a bit overscoped. There a couple small changes that would help make what you have feel more complete.
With some more polish on the camera and controls, this will feel much better to play. For one, the sensitivity was very high for me, so a sensitivity slider could help a lot for accessibility. Also, it was difficult to aim upwards because the camera was overly restricted.
Any sound effects would go a long way, too. Even very simple sounds are usually better than silence.
It would be cool to see you keep working on this! I recommend starting by focusing on one really cool level, rather than a campaign of levels.