A few points here:
*We're always being told not to harper back to the 'good old times', but it seems like Blizzard and their supporters here should take their own advice. You can't recreate the past, especially not with CRZ. The game, like I said, was very different back then CRZ is creating a very different experience with very perverse incentives.
*Cross realm anything removes personal reputation from the equation so just by being introduced the amount of griefing, ganking, camping and general ass-hattery will increase substantially. "You rolled on a PvP realm" might be a technically correct observation, but everyone spouting that is missing the real issue here. Gankers before CRZ were 'known gankers', and you could anticipate what they would be up to. These days its a pure free for all.
*Blizzard went through the entire levelling experience and removed any requirement for multiple people to team together in order to level. No more group quests. No more challenging mobs or elites. So to put it blatantly, what is the point? 'Intended population levels' sounds like corporate speak to me in order to cover their own backsides. If there is an 'intended population level', it was very likely introduced recently and specifically to justify their CRZ proposal, or in response to the wave of criticism that people weren't leaving their capital cities any more and focusing solely on instanced PvE or PvP.