Is loving others for the sake of Allah obligatory or one of the perfections of faith, especially loving what Allah loves and loving for His sake? And must love for everyone be ناقصًا (deficient/incomplete) due to their disobedience, thereby reducing comfort with them?

Love for one's family is instinctual and a Muslim is not held accountable for it. However, if the one committing the sin is a close relative, then one must detest their sin and wish for their guidance, because that sin is something Allah Almighty detests. Therefore, love for the sake of Allah and hatred for the sake of Allah, and loving what Allah loves and hating what He hates, are among the obligations of faith. The perfection of faith is commensurate with the perfection of love.