Here is the scenario:
In or before the Classical Period, a king from some Greek city-state--it doesn't matter which--first brought all the other Greek city-states together to become one unified nation. Either he or his heir then declared that the whole of the Mediterranean belong to the Greeks. First phase of the grand plan was to conquer the Mediterranean was to absorb the lands of their closest neighbors, the Roman Republic. The Republic, weak from the Conflict of the Orders, embraced their Greek conquerors with minimal resistance. In absorbing Greek and Roman lands together, Greek and Roman culture merged into one, and that includes language.
The inspiration behind this scenario is that both Greek and Roman cultures have such inspirations on modern Western culture that it's hard to decipher where Greek ended and Roman began. But what if both cultures were merged into one new one? If you mix Greek with Latin, what should I look out for in regards to grammar?
I ask this because many people are not convinced that Glosa, an auxlang already inspired by both Greek and Latin, won't be the natural answer to this question.