What extensive books on Creed do you recommend after reading the well-known short and medium-sized ones?

For a beginner in seeking knowledge, easy abridged texts like "Al-Usul al-Thalatha" (The Three Fundamental Principles) and "Kashf al-Shubuhat" (Clarification of Doubts) are suitable. For an intermediate student, "Al-Aqeedah Al-Wasitiyyah" and "Kitab al-Tawhid (definition)" (Book of Monotheism) are appropriate. As for an advanced student, "Ma'arij al-Qabul" and "Sharh al-Tahawiyyah" (Explanation of al-Tahawiyyah) are suitable. The matter varies according to the student's level and the availability of a suitable shaykh and book.