I suppose, if we define the period in question as a European Dark Age we can then reference the age that came before it as one of a multi-regional Roman state that allowed a sophisticated, literate trading empire to develop. It created an effective rule of law (at least for the time) and provide access to literacy for a large portion of its citizens and meant that for the majority of its existence its cities could exist without walls. That indicates a high degree of internal cohesiveness and stability (and the periods of chaos were remarkable for their scarcity until the crisis of the 3rd century). By contrast, the dark ages was a time of feudalism, agricultural and intellectual decline. It was a period where the great strides of literacy collapsed. It was in thrall to a stone age monotheistic cult (Christianity) and indeed one of the causes of the fall of the Western Empire was clearly the baleful influence of Christianity on the previously educated, rational, religiously tolerant Romans. An educated Greco-Roman of the 1st Century AD would probably have laughed at some of the things the Dark Age church claimed as "knowledge." He would probably ask what happened to the baths, the money, the pottery, the tools etc.I'm not saying that Rome was perfect; it could clearly be brutal, cruel, militaristic and utterly ruthless but it was a lot better than what came after, even if for some individuals there was greater freedom after it collapsed. I think if you asked a Romano-Britain whether they preferred the rule of a good Augustus to scratching together a village militia to try to stop yet group of raiders burning the village and raping the womenfolk they would certainly have cried out for the empire. I think maybe the reason we sometimes try to revise the Dark Ages into something better is because of a modern reaction to the British/American Modern Roman Empires of the 19th, 20th and 21st Century. The British Empire was a conscious attempt to recreate a form of Rome, and I believe a lot of our attempts to polish the Dark Ages are an attempt to get away from post Imperial guilt, and also to create an alternative origins myth.Of course, I do love the Dark Ages. They are a fascinating period of study; to me they are the age of the Huscarls, the Shieldwalls, the Thanes and last stands, of the Dragon Boats and the basis for Tolkien. They also gave us the Northmen, the discovery of America, and the epic Battle of Maldon.