Having yet to play A17 I am hesitant to say this but I suspect this might be a game breaking change for me. I will give it a try and see how it feels, however I suspect I may have issues motivating myself to kill zombies just for the xp they give. Most of my base designs (I'm a huge fan of base building, especially in this game) are set up to survive the BM while killing as many zombies as I can. The payoff being the loot they drop.
Additionally I tend to kill zombies, yes for the xp but more importantly because they have a chance of dropping decent loot. Nurses could drop antibiotics, military zombies could drop guns. I feel there needs to be a payoff especially if zombies are (and they do look to be) a lot smarter and perhaps more difficult to kill. This change will likely result in me (and likely many others) avoiding zombies more than engaging with them.
Not having corpses everywhere is a nice change I have to admit, however it really seems like this change plays more into the style of the people who prefer to explore more than base build. I do explore as well, and having less to deal with w.r.t zombies while exploring sounds quite beneficial but as a base builder this really detracts from the appeal of the game.
On an unrelated note, would anyone be able to tell me: how are voxels/blocks being saved if not with an ID? Having done some work in Unity myself I am very curious how this was achieved.
