So yeah, it's been a long time since I've updated this thread. The project isn't dead, I've just had a lot of other stuff going on so it's been shelved for the past six months. With the release of Unity 5, and some life stuff finally stabilizing, I'm finally ready to continue. The project has been updated to Unity 5 and all the resulting bugs from that transition have been squashed, so it's more-or-less in the same state as before.
The scope of the original concept (a large open world with lots of missions, voiced NPCs, crafting, etc. etc.) has proved to be a massive undertaking, far too much for one guy/a handful of guys to execute. Starting now, the focus will be on developing a defend-your-base game on a much smaller scale than originally called for. The player's main goal will be to survive for a set period of time, say 45 days, until the military can get around to providing evac.
You'll be tasked with holding and defending your position (your cabin/compound way out in the woods, but sadly locked within the anomalous region) from the mutant hordes. During the day (when the hordes are less aggressive) you'll be able to scavenge the surrounding countryside (a much smaller world than originally planned) for basic resources like food, water, and medical supplies, as well as building supplies for fortifications and repairs. You'll also be able to evac/rescue NPC refugees who are camping in the wilderness, a few with skills you can leverage to unlock better upgrades for your compound. You will also need to manage food and water supply/production to support your growing population.
Missions will be handed to the player via radio and NPCs you'll encounter in the world. The government may also communicate with you via radio to warn of an approaching boss monster, or to provide intel on supply drops or suspected refugee locations.
There's a lot of work to get there, but this is doable. See you guys in a few weeks.