dekman
I know it's been a month.. how's the progress?
This looks pretty dang neat. Great job on the graphics. Only thing that looks a bit odd is the stepping of the player. The legs are in certain cases on a 90 degrees angle with the players upper body. That looks really weird.
I think the NPC thing is very awesome! It gives you the feeling you're not alone (like in every other zombie shooter) and makes it a bit more fun to fight 'together'. For a second I thought I was playing with another human player, imagine how cool that would be; to play with your friend.
Maybe coop mode with a friend could set the game apart from others. Like you said, right now it's a bit generic and you want it to stand out if you want it to be successful. I was thinking of an app, I'm not sure which would be more difficult to pull off to achieve multiplayer; desktop or app.
Oh, and the red blobs that fly towards you when you kill a zombie, I couldn't figure out if I was being hit or that I got a point or something. In any case, perhaps on collision have a '+10' graphic displayed top left of the player, or a blood splat if it's a hit. If you didn't already, getting late, memory failing.
It would be a shame to see this project get stranded. I know how you feel; the project has taken a lot of your energy (kudos for working on it for a year) and it's becoming a drag.
Hope the comments here give you that needed boost. The game looks and handles professional, you can see the effort put in. So don't let it go to waste.