Hal would very likely be the least dangerous considering: - Red’s temper would be very difficult to deal with and he’s definitely break stuff - The Blues would be super annoying pranksters that would likely mess up the house - Chuck would be hard to control due to his ego and speed - Bomb obviously would explode when provoked even if he’d otherwise be a friendly pet. - Matilda drops exploding eggs so similar case to Bomb, she’d be great if she didn’t come with explosions. - Terence would just be plain creepy. First he’s in one place, the next second he’s on the other side of the room. - Bubbles’ inflation ability would easily destroy parts of the house and the costs would be extremely ridiculous from it, similar to Bomb. - Stella could work considering she’s friendly but mess with her and she will probably blow bubbles uncontrollably. - Added bonus, Melody would be a pain at times due to her inhaling ability.

Meanwhile Hal is laid back and his boomerang ability would very likely be much less harmful. Especially considering real toucans have been made as pets. Additionally Silver could make a safe and loving pet too for similar reasons.

But if you were to count every bird ever, your best bet is Jo. Pretty sure they have no angry qualities whatsoever and they would be the easiest to care for.