When Creating a FPS game what basic rules would you add?

We should add:

Explanation:

Anything red must explode if shot. Fixed mounted guns must always face away from any potential flash points and be pretty much useless. Never bring a gun to a knife fight. Never run into a room that you have just thrown a flash bang into as the grenade only effects you.. Create a world that invites, encourages, and rewards smart thinking.The game world is the real world.packages are the best way to draw out campers, pop one out into open areas and pick people off as they inevitably try to steal it from you, then when they are all dead still in and claim your UAV (or ammo crate more often than not).The only thing you can ever rely on your team to do is, give away your position, run into your line of fire and friendly flash you.If you pick up the sniper or any other power weapon someone on your team will always teamkill you for it then miss with every shot they fire using it.