Jolie has flaky ideas, but I am not gonna judge her motivation as bad when there is no evidence to show otherwise. It dosen't appear she pawns this kid off to some nanny to raise, she takes him with her almost everywhere.
I don't know if that makes her a good mother --- Michael Jackson took that monkey around with him everywhere for a while too. Maybe she is an okay mother -- I don't know but her relationship with her brother would make me wonder if she was raised with any values to be be able to be a good parent.