You didn't give anyone even a glimpse of your game, you want us to provide you feedback for free AND you're asking us to do something as outrageous like signing an NDA? We don't even know you!
What you're asking is way too much. I suggest you create some sort of demo, post it here so people can play and give feedback without having to jump through hoops. And if you're really worried, you can sitelock it to your own domain.
Best of luck!