add random events, like every now and then like lets say, when its raining you start getting cold, if you get too cold you start feeling sick, when you start feeling sick you cant do much actions and are slower, the only way to revive is with either medicine or staying out of the rain, add weapons that have tactical advantages, lets say, if a player acquires a pistol with low health on it, you cant hurt as much, you can craft or repair to make the gun get better, add the ability to add attachments, make a way for players to have transmissions, like lets say, a global transmission, a local transmission and a private transmission. just some ideas y'know