I have successfully used this design to increase the number of villagers in my village, so that i have more trades to choose from and will spawn more golems, and I wanted to share it with the community. It works under the principle that villagers spawn in proportion to the number of "Usable Doors". This particular design is based on spawning villagers in as efficient a manner as possible, using the least amount of space and resources (since i designed it to be used in survival, or in a server). It can be endlessly expanded either horizontally or vertically, until the height cap.