Psh, I went to Nostalrius even though there were hundreds (thousands?) of people aready decked in T2

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Kronos is running War Effort (full thorium, laughably litte purple lotus, 30k/90k copper bars, can't remember the rest), and frankly there's been so many people coming lately that the original populace is a minority.
While you're right it's not a fresh start, the majority of people there right now are leveling, so you wouldn't be at much of a disadvantage.
Interesting thing the Kronos admins did, btw, they a) removed playercount from their web b) scrambled /who so you can no longer filter it for c- z- r-. Therefore it is effectively impossible to correctly read the population of the server now. The fear of Blizzard is real.