Great game. A cool thing to add in the sequel would be easy and hard modes: easy is the way it is now (where spam-clicking is a viable option), and hard where mistakes are penalized by loss of time. Just a suggestion.
I agree with kephera, a zombie survival mode would be a nice addition to number 5. A larger map with a non-static camera, going around finding weapons, sounds pretty cool to me.
Personally, I think "Bang" grenades are too overpowered. Not only do they render Flashes and Stuns useless, but they make you completely lose 3 turns, plus the effect can stack. Also, the fact that ALL the enemies use them in stealth levels make them more difficult than they need to be. I say you should lower the effect time to 1, but keep Stuns and Flashes at 3.
Me with my goddamn twitchy hands kept hitting back on the mouse...doesn't help that its right where my thumb's supposed to go! Anyway, great game, time well wasted.
Pretty awesome, but the prices and buying seem a little messed. Either absolutely noone buys it, or everybody buys it, no matter how small the change in price is. Still, great game. 4/5