I agree with you, icarus. It is an alternate universe after all, and technology in different areas will advance at different speeds. But since even by Iggy's own estimation, its been 2000 years tops since the dawn of prehistory. Judging by the fact that according to OTL it would still be 1000 BCE, (and that's generous,) technological progress (or technoflation) has increased at a slightly faster rate, IMO.
That would bring us to a pre-Roman or late Hellenic World level...perhaps 500 BCE. Contrary to what das has said, naval technology hasn't really advanced to anything farther than that, despite its patronage by the Valin nations.
Just look at the Punic Wars. You had fleets of over 100 Quinqueremes (which are about as large as the largest ships fielded by Veritas or Khemri) engaging in battle, and armies with sizes (at times) of almost 50,000 people clashing. The Battle of Trebia was on a far larger scale than anything we've seen yet here.
At least in terms of army and navy size if not population, (I personally think that in the next age, one eco should buy 2000 troops to account for this,) LINESII lags a bit behind our world.
Conversely however, architecture and city building, siege warfare, and other more peaceful domestic pursuits seem to live up to their OTL comparisons, thanks to the efforts of Veritas, Khemri, and the Citadel mostly.
This is my justification for pegging the current date of the NES in OTL terms at 500-700 BCE.
EDIT: I almost forgot the Battle of Cannae, where there were at least 80,000 Romans and Latins, and 45,000 of Hannibal's troops.