If they had depicted Roman life as it truly was, the series would have been XXX rated. 
While certain things are creative license, I do think they have done a reasonably good job portraying the spiritual truths of the Gospels. The creative license has brought a real human presence to the story with the group dynamics in focus a little more which, sometimes can be lost when reading the Gospels. The disciples and those who followed Jesus were a real motley group when you think about it, fishermen, a zealot, a tax collector, women, we tend not to think of how they dealt with each other as the focus of the Gospels is on Christ (where it should be) so I find that dynamic interesting and thought provoking.
While certain things are creative license, I do think they have done a reasonably good job portraying the spiritual truths of the Gospels. The creative license has brought a real human presence to the story with the group dynamics in focus a little more which, sometimes can be lost when reading the Gospels. The disciples and those who followed Jesus were a real motley group when you think about it, fishermen, a zealot, a tax collector, women, we tend not to think of how they dealt with each other as the focus of the Gospels is on Christ (where it should be) so I find that dynamic interesting and thought provoking.
The biggest thing that would be impossible for the writers to pull off is the way Jesus gave out his "back pocket sermons" that the Apostles were to learn and repeat.
These sermons, like the "Sermon on the Mount" are poems and constantly repeated. (Matthew records most of these sermons the best and most accurately of the 4 Gospels which is why his name was changed from Levi (of the tribe of Levi) to Matthew.
Luke has several sermons recorded as well but retransmitted and reformulated for a Greeko/Roman audience who would be lost or insulted by Jewish cultural norms.
Mark (Peter's stories as Mark remembered Peter retelling them ad nauseum) had a different focus as does John's Gospel.
Jesus also was not tall and thin. He became thin towards the end of his tour (too many days fasting) but he was extremely muscled by his occupation in construction. His hands would have been extremely calloused to start with but became softer as he stayed on ministry tour.