Thanks for your feedback! Godot engine has some issues exporting to web and probably that is why the retry and game over screens are broken in web builds. I tested on Windows and Linux machines and it seems to be working.
Thanks for the camera shake video link. The hit feedback thing is requested by almost everyone who played this game. I've tried out camera shake on a test project and I can easily add it to this game. Will surely do it once I get some time.
I am really bad at UI stuff and that is why the main menu seems so dead :-p But I'll see what I can do about it.
That leader board thing is really an cool idea and should not be that difficult to achieve. Same for the cut-scene thing too. The only issue is time. But I think this is worth doing. I'll most probably re-write the game from scratch again. The code right now is just all over the place :-)
Glad that you played it and posted you thoughts. Now I feel motivated again to work on this.