In what order should I read the various Buddhist scriptures?
I have read MN, then SN, then AN - so that's another way to sequence it. Then you can read Questions of King Milinda.  Then Tattvasiddhi Śāstra by Harivarman also known as Satyasiddhi Śāstra, Then Vasubandhu's Abhidharma-kosa. Then the Rice Seedling sutra. Then try Vimalakirti sutra. Then Diamond sutra. Then Heart sutra. Then Nagarjuna's Mulamadhyamikakarika.