They got round that a bit by having the player be a sort of prototype Big Daddy, who was more agile and human like. You still had to fight other Big Daddies to get Adam, but they added a new option to temporarily “adopt” their Little Sister as well as harvest or rescue them.
I haven’t played 2 in a while but from what I remember the gameplay was fairly fun, especially with the drill weapon.
Don’t let the fancy bottles trick you into ignoring the potential side effects though, you don’t want to get too spliced up.