1.) You shouldn't be allowed to log out when in combat or near other players.. The way WoW handles this is, there is a timer, say 20 seconds, that the player has to sit through undisturbed before they are able to log out.
2.) One should be able to lock zombies outside of buildings.. At least temporarily.
3.) Melee weapons often give off bullet sounds which is extremely confusing. This obviously is a major necessity to fix.
4.) Night time should have at least some color. The 24 hour cycle must go as well. It simply isn't feasible that some players can only pay at ingame night or day.
5.) At times there is nothing to loot in the whole game and then there is too much. There should be a more balanced system, but I can only imagine this should be fixable over time when a formula makes itself more apparent.
Amazing game, nonetheless, but these are my woes.