This is great ! I like First person shooters with procedural generations, but hate roguelike FPSs due to their heavy RPG elements. I like this one for simply focused on shooting, looting, and explorations.
I suggest to improve the gunplay by adding more effects to the gun firing, spawning more enemies with guns, and Add a short stun for them when they got shot like the enemies in classic FPS games did. Since It's a shooter, gunplay is the most important part of the game after all.
Adding more various environments to the random map generation and making it endless with keep increasing difficulty would be fine too.