Given the overwhelming view of the community (and the fact that it's true) that zombies are secondary and not particularly threatening, adding some spice to fighting them could help. Once even mediocre gear is obtained, managing zombie attacks is rather simple with the only excitement occuring when they warp through walls or hit you through magic portals that only Zeds can see. Here's my suggestion: Gunfire triggers a horde. A pack o' zombies. A straight up mess of 'em. You get the idea. Groups of 10-20(spitballing) zombies spawn en masse near the gunfire and rush the area. There would have to be a cap at the number of groups spawned in an area due to the high volume of shots heard in places like Cherno/Elektro. Additionally, a timer between spawns would have to be in place so each shot while fighting them wouldn't cascade the numbers on you. Add this horde to typical gunshot aggro and you can have a fairly large cluster of zombies rushing your position. It doesn't really change their difficulty or make shooting all that more dangerous but it will waste a ton of ammo cutting them down and if you aren't well armed, it could get dicey. I don't want to see the addition of 'special' zombies or any of that but a group of two dozen zombies running in a pack down the streets at you? YES PLEASE. Apologies if this has been posted before, searching revealed nothing similar.