Why? With perfectly awesome and free technologies like Unity, you’re setting yourself up for failure by spending hundred hours putting together something that has already been created for you.
It would allow you to focus on making the best game possible, instead of wasting countless hours re-inventing the wheel.
IMHO, that’s the first, and largest, mistake this project made.
Furthermore I agree with others that it simply feels ‘uninspired.’ Maybe less hours spent on the engine and more spent on the content would’ve made the game more notable.