One of my main concerns was that much of the archaeological evidence for the imperial cult post-dates Paul. In a recent article, Colin Miller reviews the archaeological evidence in detail and has the same concern:
"[M]y aim in this article is to explore which of the cities in which Paul worked, in Paul's time, had some relation to the imperial cult, and what that relation was. Is it true that the emperor cult permeated life and helped make up the very fabric of reality in Paul's world? Is it true that in the time of Paul's mission the emperor cult held the empire together? Is it, more basically, true that "[i]n any city that Paul visited, evidence of emperor worship appears repeatedly in present excavations?" [quoting Crossan and Reed] I argue that all our evidence points to a negative answer to these questions. The archaeological evidence reveals that, in the cities Paul visited, in Paul's time, the emperor cult was marginal. In more than half of Paul's missionary cities there is no evidence of the imperial cult at all. In the others, I will show, the emperor was only one cult alongside many others." (Colin Miller, "The Imperial Cult in the Pauline Cities of Asia Minor and Greece," Catholic Biblical Quarterly 72.2 (April 2010): 314-332, here 316)Looks like an important article!