A good town should provide for it's people and the best way is free stuff!
Plant farms are one of the most simple things to give your town plus if you are good with redstone there are plenty of ways to make the harvests super awesome!
Cactus farming can be really easy and effective plus use pistons hoppers and sand to create an auto harvest.
Wheat potato and carrot farms are essentually the same . Flood it with water to auto harvest.
Melon and pumpkin farms are great but I dont have a redstone tip for you. You could try sticky pistons but I haven't tried it yet.
Nether wart farm!
Animal farms are great as long as your citizens feed the animals
Types are sheep(feed wheat) cow(wheat) mooshroom(wheat) chicken(seeds) pig(carrots) horse(golden apple)
And everyone loves grinders use the classic method with water and signs but make sure you have an elite in this town to get lots of spawners.
Pvp arenas!
This is a simple small list of them feel free to add!