I've hear d a lot of people say it's like the first one in quite a few ways. Like the bosses.
The bosses in the first game drove me bat shit insane. The shooting was terrible when you were fighting anything that wasn't a zombie. The zombies moved really slow, giving you time to work the reticle over their face and go boom-boom-boom. In a boss fight, you'd have a guy throwing grenades at you, and you're standing there trying to pop off a shot at him. I died a lot with things like that.
Or how you'd go through the court yard and see these gangbangin' thugs running around in a jeep, mowing everyone down. Even IF you managed to kill them, they'd just respawn the next time you came. It felt pointless. They were a huge pain, and even if you managed to finish them off, it didn't matter.
Saving survivors sounded fun at first, but I quickly got fed up with it. I'd be trying to fend off a fresh crowd off zombies with a base ball bat, crow bar, hammer, bench, or SOMETHING and the survivors would always get in the way. If I ran out of ammo, it was super hard to get zombies off of them without hurting them. They did a terrible job of defending themselves, and I'd watch them accidentally smack each other around until they died or just disappear in a circle of zombies because they strayed away for some reason. The map didn't really do me much justice, either.
The timer on the game made me feel like I had to star rushing through things at some point (until I quit), because sometimes I'd just want to have fun and kill zombies in weird ways. I wanted to dick around in-between missions, but then I felt like I couldn't. A mission would expire, the clock would be counting down, it'd be night time soon, I only had three days, etc, etc. It just added a layer of pressure that felt unnecessary and got in the way of my enjoyment.