Holy crap, this is fun.
Contrary to your advice, I started on Normal. I always start games on Normal, because I know Easy is too Ease and Hard is for when I want to challenge myself.
No, I wanted to see this game operate in a natural progression as per the standards of said game and have it show me the ropes. It did just this and I found myself thoroughly enjoying myself despite the unruly headache I got from a cold. A turn-based-strategy game involving pitting survivors of all types in a city against the zombie apocalypse? Brilliant. I don't mind telling you that I've been at this for hours and I'm not bored.
It IS tricky to master at first, but I've been able to get my territory to expand with both people and resources being taken in a good way. And indeed, I have gotten to enjoy the little surprises you put into my city map and all the random funny bits that are just in there. I have found the music to work well with the game and the mechanics to be fully operational.
There is...one qualm, however. I found a problem when I was making use of a school: My leader - I had only one at the time - was somehow accidentally turned into a soldier. The selector for the school had - for some reason - prioritized him to be trained, though I have no idea why since I needed him for recruitments. Suffice to say, I just retrained him again, but why would that even happen? It seemed wrong.
Anyway, this is an EXCELLENT zombie game. High five!