Honestly once bandits with guns come in the zombies will be almost a non-threat, I mean a npc with a gun is going to be much more dangerious than a slowly shambling zombie at anytime, even at night, the bandit will just shoot you. In a way I don't want bandits to come to the game because it'll trivilize the zombies even more than they already are.
As fr the AI IMO zombies should see traps as air blocks and try to walk thru them, they are mindless corpses, they shouldn't even know what a trap is, nor should they be able to path around them. In A17 I mostly fight my horde nights in the open on a street, as like its been said they tend to just avoid traps so they are a waste of resources. I have a vechicle with me usually, and just hop on and run away a bit when they get to close then I get off the vechicle and kill them till they start getting to close again, repeat till 4am 0 damage to base, but more risky to me. Yeah I could just keep riding the vechicle and ignore them, but the horde night is like a exp present just waiting to be opened.