597. Axes, hammers and other metal tools with wooden handles shouldn't just break the way they do. Proposed solutions:
a) A broken metal headed tool is replaced with a metal head (eg Axe head, Hammer head, Sledgehammer head) and a "broken handle". The broken handle can be repaired as normal and become a tool handle. You can then haft the tool head to a tool handle, consuming either ripped sheets, nails, wood glue, or some combination. The durability should reflect the quality of the items used. (Alternatively, just having Tool Handle and giving it the "Broken" condition)
b) A broken metal headed tool is replaced with a metal head (eg Axe head, Hammer head, Sledgehammer head) and a "broken handle". The broken handle is junk wood and can be burned for fuel. You can create a new tool handle using Carpentry (maybe lv 2-4?) by using a Knife on a Sturdy Stick. You can then haft the tool head to the tool handle, consuming either ripped sheets, nails, wood glue, or some combination. The durability should reflect the quality of the hafting items used, but should be high as an entirely new wooden handle is being used.
Edit: Durability should also be reflected by Carpentry Skill.
598. As above suggestion, but you should be able to un-haft the tool somehow (saw? knife?), to re-haft it with new wood to improve the durability, and remove any "repaired x times" modifiers.
599. Hunting Knives should be re-haftable as well, as it's extremely unlikely for the actual blade to break on a good quality hunting knife, and the metal tangs are quite large, almost handle size on their own.
600. Crowbar durability should be greatly improved. I don't think they should be invulnerable as others have suggested, but given their in game rarity, and how sturdy Crowbars are in real life, that should be reflected.
601. Crowbars should be able to (noisily) pry open a locked window, with some chance to break it. Crowbars should also be able to (very noisily) pry open a locked door, but the door should not be able to be closed tight anymore. I know windows was suggested before, but have not seen the door suggestion yet.
602. Bigger trees. Stuff that blocks your view even if you're on a second or third story. The bigger trees could take longer to chop, but could yield more wood and twigs depending on their size.
603. Dragging corpses. Right now it's a huge pain to move Zombies, as they take your primary and secondary slots, and you have to do manual inventory management to drop them, often not exactly where you intended. If we could instead "latch on" (maybe by holding spacebar for a few seconds or something) to a zombie corpse and be forced to (noisily and messily) drag it, with our backs to where we're going, it would be quicker and more apparent where we're actually leaving the corpse.
604. Wheelbarrows, Carts, Shopping Carts, etc. This would make moving heavy things easier and safer, and could use a similar mechanic as the Dragging corpses, where your hands are busy until you let go of a button (eg spacebar). These devices wouldn't be able to go up and down stairs without picking them up. You wouldn't be able to sneak while using them. They could hold corpses (maybe 1-3 each? or depending on type), furniture, random loot, dirt (for wheelbarrow), and could make noise depending on type. Shopping carts being the most noisy but also most common. This would add a risk-reward element to looting as well, of whether it's worth having your hands full and making more noise to make loot runs more convenient. Strength could determine how much and how fast you could push, as well. Different terrain could affect mobility (eg shopping carts would be very slow on non-pavement, wheelbarrows would be a bit slower on grass, but not much.)
605. I think this will be part of the animation update, but tripping (corpses, fences, random crap on the ground) or slipping (on snow, wet or icy pavement, oil, or blood) while sprinting, and getting knocked down by zombie attacks (instead of bitten or scratched). These could be affected by the nimble trait, with maybe strength and/or fitness added in to avoid getting knocked down.
606. Fishing should be possible year round. If the water isn't frozen over, the fish are still mostly active. Even if the water is frozen over, Ice Fishing is a long standing tradition of many cultures, and can catch quite a few. Reducing the rates is fine, but don't make them 0 or almost 0.
607. Add a smoking/drying rack to Carpentry / Metalworking, which must be placed over a camp fire. Given time it can smoke meat or fish, dehydrate veggies and fruits, dry towels, etc. You'd have to keep an eye so it doesn't overdry (can use a similar mechanic to burning). Dried food would reduce thirst, and lose some of its initial hunger value / nutrients, but have greatly extended or indefinite shelf lives.
Also honorary mention to something that's been suggested before: Bikes. Please please please.