I prefer a hamster. Because birds are loud, and while your sleeping or when guests come there'll be this chirping noise in the background and they might get a headache. ._. xD They also die easily if you don't give them much attention, like what my cousin did to her birds, and you'll eventually get bored of a bird, just watching it chirp, unless you get a talking parrot, which would be amazing, :D but most likely not going to happen. Birds also may escape easily, depending on their size they could go through the spaces in the bars, especially if you're trying to get them in a new cage. I know that's kind of dumb and probably won't happen, but it could, you may never know.
The reason I prefer hamsters are because they're usually quite energetic and you'll probably never get bored of them. They also don't need a lot of attention, they still can play in their cage and run around, especially if you give them fun small hamster equipment so they can play by themselves if you don't have time to give them attention for a bit, and if you put another hamster in the cage, it's most likely they'll communicate with eachother like any other human or animal and will get to know each other and make friends, then you're not forced to give them attention, because they are busy playing or with their friend whenever you're not around, unlike birds. They also are very lovable and you can actually sit down and hold it in your arms, pet it and feed it and bond with it, and birds can also bond with one person, as you said. You can even play with your hamster as long as you're sure it's safe.
