It feels like it takes 30 minutes just to get out of the early-game slog of a mission, but it can end in the blink of an eye. But if a single zombie makes physical contact with a house, he can infect everyone in the building in about 2 seconds, which spreads like wildfire even if you have attacking units nearby actively trying to kill the zombies. Resource generation is slow, and if you're not actively microing your units, it feels like there isn't much to do other than sit and wait for the train to come by and give you some gold so you can continue building. The game is somehow too fast and too slow at the same time. Imagine playing a match of a MOBA, but your character has no abilities and gains no levels, you just have to auto-attack and kite creeps for 30 minutes. The hero missions in particular don't seem to add anything meaningful to the game.
There's something in this game that makes me want to like it, but there's a lot that's just.