Demakes are so seldom well done. Especially when you're trying to capture FPS on older systems like this. This top-down is so so good! The pace is great. The artwork is great. The controls are great. The level design is great. The dialogue gives story without bogging down gameplay.
I'd pay for this game once you're done. For real! I know the legal stuff for a demake may make that tricky. But if you finish this and have fuel for more, you've definitely got the skills and drive to make high-quality games.
I see in other comments where you stated recently having had twins! Congratulations! Hope you're enjoying them