Just MHO. However after having 4 cats (that I loved) at once time. I would say chickens and cats are about the same. Both train easily with treat food rewards and a little time.
I have 20 chickens right now.
I think dogs are the most time consuming. They need to be walked and in my neighborhood that means picking up any poop that may arise from the walk. This of course means multiple walks or trips to the "dog park" so the dog gets the exercise and playtime needed. They also need time spent...