For me, babies are easier. Puppies can still keep you up at night (mine did until she was 5 months, she has seperation anxiety, so being caged... ) Puppies get into anything and everything, and make messes in the house until you get them trained. Babies just lay there, until several months when they finally roll, then eventually crawl. And their messes are contained in a nice diaper.
Personally I prefer puppies than babies. 1. Babies can be harder to take care of and can be more expensive. 2. They require more attention than puppies. 3. You can't just put food in a bowl and say "well here you go!" lol Well this is just my opinion on itbut hey it could be different for others.