While constituent order was quite flexible in both Classical and Koine Greek, sound arguments can be made for considering certain orders as more basic than others. In “How Does a Basic Word Order Become Ungrammatical? SOV from Classical to Koine Greek,” N. Lavadas argues that the Hellenistic Koine was pivotal in the eventual disappearance of SOV as a grammatical order. (That order is ungrammatical in Modern Greek.)
- How Does a Basic Word Order Become Ungrammatical? SOV from Classical to Koine Greek, Studies in Greek Linguistics 35 (2015) pp. 323-335.
You can read the article online at Aristotle University of Thessaloniki. I have added it to the bibliography here at Greek-Language.com.