Ability to go prone, quality scopes to be able to zoom in adequately, night vision goggles. proper camouflage gear, (military uniforms, ghillie suit and so forth) bullet drop, binoculars with range detection, a more emphasis on ranged combat / avoiding detection. Also I would not want to see the zombies removed, however they drop way too much stuff. Stuff should be really hard to come by / craft.
Also once you managed to craft a number of slots on a weapon, it would be logical that the next time you craft it, you should have a high probability of getting a number of slots close to what you’ve previously crafted if not higher. Also I want to be able to attach / remove mods on the fly (at least the silencer, the rest can require a workbench).
In it’s current state the game feels way too easy, not interesting enough, if not downright boring… people are bound to lose interest in a short time. Definitely NOT going to buy the game in its current state.
OK, screw the scopes, how about less sway on the bolt action rifle? I don’t see why anyone would want to use that over an M4 in the current state.