All textbooks I was able to consult introduce construct noun morphology before pronoun suffixes on nouns. This is a logical way of proceeding since suffixed nouns are classified as construct.
(1) Previous students struggled more with pronoun suffixes than with anything else, so starting them earlier would give more time to practice.
דָּבָר > דְּבַרְכֶם > דְּבַר
דְּבָרִים > דִּבְרֵיכֶם > דִּבְרֵי
קָדוֹשׁ > קְדוֹשְׁכֶם > קְדוֹשׁ
מְלָכִים > מַלְכֵיכֶם > מַלְכֵי
1) propretonic vowel reduction
2) rule of Shewa
3) an a-vowel before כֶם/כֶן is always short
No reference to construct forms needed.
0) add sffx דָּבָרְכֶם
1) vowel red. דְּבָרְכֶם
3) make a-vowel short דְּבַרְכֶם
Example: דְּבָרִים
0) add sffx דְּבָרֵיכֶם
1) vowel red. דְּבְרֵיכֶם
2) rule of Shewa דִּבְרֵיכֶם