You managed to put a lot of features in this game ! The concept is really cool, and the shooting mechanic is quite well made. I like the idea of having to choose between having light and shooting, it's quite reminiscent of the gameplay of Doom 3 :)
To make things a bit less tedious I think you could have increased a bit the speed when pulling the light, it takes way more time than necessary to progress in the levels. Or maybe you could have increased the speed bonus you get with upgrades, it felt quite weak currently. But that's just nitpicking, other than that it's a pretty solid entry !