How did Abd al-Malik change the administration of the Umayyad caliphate?

The fifth Umayyad caliph, Abd al-Malik, significantly centralized and strengthened the administration of the Umayyad dynasty through several key reforms:

• Arabization of Administration: He replaced local languages with Arabic as the official language of government throughout the empire. This shift enabled Arab Muslims to more easily control state affairs, whereas previously, many government officials had been non-Muslims.
• Monetary Reform: He introduced a "reformed coinage" of gold, silver, and copper. Unlike the previous coins that mimicked Byzantine or Sāsānian designs, these new coins featured Islamic inscriptions, such as the profession of faith and verses from the Qurʾān, reflecting the principles of the faith.
• Centralized Authority: Unlike his predecessor Muʿāwiyah, Abd al-Malik adopted a more autocratic style of governance. He abandoned the practice of consulting a council of advisers, choosing instead to reserve all major decisions for himself and closely supervising state affairs.
• Administrative Appointments: He relied on efficient, albeit sometimes ruthless, administrators like al-Hajjāj to pacify restless provinces and maintain order, often utilizing Syrian troops to secure control over volatile regions like Iraq.