The principle lives on even after the death of a leader; that's why it will all depend in the next successor whether he'll stop this madness or start fresh with a new foundation.
Based on an article (and wikipedia), Abdullah Qardash is placed as the next successor. (source)
Abdullah Qardash is from Tal Afar, a predominantly Sunni Muslim city in northwestern Iraq. He is a graduate of an Islamic Sciences college in Mosul and had served as an army officer during Saddam Hussein’s regime. Close to al-Baghdadi’s deputy, Abu Ala al-Afri, who was killed in 2016, Qardash was nicknamed the “Professor” and the “Destroyer” and was recognised as a brutal policymaker in the group. Described by some security analysts as cruel and authoritarian yet popular and well-respected among other IS members, Qardash was responsible for eliminating those who are against al-Baghdadi’s style of leadership.
Qardash shares a history with al-Baghdadi. The two were imprisoned together at Camp Bucca detention centre in Basra by the US forces over their links to al-Qaeda in 2003. Camp Bucca was where al-Baghdadi forged close alliances with other inmates while refining his vision for the so-called Caliphate. Qardash had served as a religious commissar and a general sharia judge for al-Qaeda before pledging his allegiance to the IS.