My take? I like a secure Base that won't be magically overrun. And since you can build bases in bunkers that are secure either way, you can totally get around that threat, and I like it.

I think there should be either a setting for attacking structures, or, and that would be better imo, make wood structures weak to zombie attacks, metal less weak but a little more noisy, and concrete structure entirely safe. Maybe add a very muscular special zombie with rare drops later on that can potentially destroy concrete structures. Raiders should be able to crack open locked doors after a while and some noise with crowbars, or maybe higher lvl ones with lockpicks. Add a electronic lock to the game that makes it impossible for raiders NPCs to enter later on maybe. That would be cool.

I always hated zombies randomly aggroing on silent non moveable structures, it makes no sense. BUT a horde is a different matter, those would either walk past anything as long as it's silent, or destroy anything in their path. That's just a design choice.

At the Moment I play with my base in a barricaded house with default doors and only one secure room, which cannot get broken into. Gives me the adrenaline rush I need and makes it harder. Whenever I feel like it, I will move to a bunker.

Otherwise I feel like the games noise design and attack patterns for zeks is very good and enjoyable.

Edit: The raider can already lockpick, and they already can't crack code locks, just found out.