Hey. I think that the game idea is awesome. You can add some abilities and melee weapons, and it would be really cool to play.
Sneaking and combat is very engaging. There is a game that is called Hotline Miami that is very successful. You can check it out and take the best things from it.
I made a video about me playing your game. I hope you will like it. Also, I am hosting a jam(with prizes) that is going to happen at the end of the following September. The video is here