I like pretty much all of those ideas, however. Swords, katanas and batons should keep away from DayZ in my opinion. Golf clubs and Baseball bats seems like cool idea (maybe like 1k-2k damage and knocks people out if you hit the head?). I would like to add: More movable things, like trashcans, maybe cars pushed from back. More hiding places and different kind, shaped, and sized trees/bushes. You have seen in the game pile of logs, maybe more of those but bigger piles, maybe you could build those piles yourself? Fallen trees in the forests. Chainsaws could be cool too as you said. Really big thing i recommend is a chance to kill people with hunting knife for silent kills. Also shooting in car with pistol would be cool, especially if there is tinted windows, you can hide in backseat and wait till someone comes in and ambush him with pistol.
