Imagine you are a journalist in the roman empire. write an editorial in which you comment—favorably or unfavorably—on constantine’s decision to move the capital of the empire.

This is a strange question as there were no real journalists in the Roman empire as we know them today :) What existed in their times were historians who would write down the history of the Roman Empire from their perspective and eyes. 

What one could write here would be that the people who lived under his role in the Eastern Roman Empire probably or most likely viewed this decision as a favorable one considering he essentially created a new important trading and commerce hub in their part of the Roman Empire.