I also live in a flat city. Our high point is the top of a bridge going over a highway. Low point is a lake. About 200 feet elevation from one to the other. Two of my bikes have 3 speed hubs, Sturmey Archer AW. On my main commuting bike, it's like having a 2 speed hub, since the 3rd speed is rarely useful. On my winter bike, I have a large cog, and use 1st gear as an "extra low" gear for when I'm trying to fight my way through deep snow, but normally it's also like a 2 speed.
There are some rare old Sturmey Archer hubs with closer spacing, but it might be hard to find parts for them.