So I am at a point where I can pretty much win every time. The game is great and I look forward to updates and the game maybe having more difficulty and deepness but I think multiplayer would really make this game shine. Here is what I see:
Multiplayer matches with up to 4 players. The map is a bit larger with more resources but a bit more random. Each player starts in a similar but different house with some randomness and spread out across the city so they each have access to different resources. From there the game could play about the same with the difference of being able to send one person out on a trade mission during the day. (much how the npc guys do it.) During the day you can't go hostile and the person who trades can't do anything else that day. At the end of the day When every player is ready (Think Civ) So each person can have separate time and it doesn't have to turn it into a panicked click fest. Once everyone is ready for the night turn you still only get one scavenger and he could end up in the same area as the other players or he could even invade their home. If you invade someones home then the computer would take care of the ai for your defense. Defenses should be a bit more deep like deciding what doors to barricade and maybe even traps. Players could become allys and just trade or maybe attempt a take over. It would add endless replay ability and I don't think it would change the feeling or pace of the game much.