This game was a little laggy for me (which is possibly my old computer) so I struggled to set up traps and defences, and especially had no time to do anything decent before the zombies were upon me on all sides. I would have liked a little bit more starting grace, such as what you get in some tower-defence games, where it's paused or the timer is very slowed to give you a chance to set up your defences. I also found that sometimes I would click on a resource and it wouldn't activate so I'd end up placing the wrong item in the wrong spot and not realising at first because after my first game it seemed to me that it would be easier to play zoomed out but then I couldn't really see much of what I was doing. Other times I "placed" things but they didn't show up (yet the resource-remaining number went down).
I would have liked it if the game sort of ramps up so instead of 200 zombies coming at you at once from every possible direction it's a few at a time so you can learn (and breathe), with the difficulty increasing over time. I really love the variety of offensive and defensive weapons but I found I was just clicking on whatever was visible to use because the UI was too slow as the zombies got closer and closer and I realised I had, for example, gaps, or I'd placed something awkwardly and they were just walking around it. (Pathfinding was therefore really good! Those zombies are too smart!)