I'm continuing my levelling on Nostalrius-PvE on and off, but it's extremely slow. Now, Vanilla levelling is slow by default and generally I consider that a feature rather than a flaw, but the high population on Nost really makes things harder than usual.
I mentioned in my previous post that you might as well forget about doing any quests that require you to pick a specifically spawned item off the ground, but finding mobs to kill is hard as well. For the purposes of getting a kill quest done, this can be alleviated by grouping up, but that only goes so far. (For example I went to Elwynn and found the mighty Hogger being spawn-camped by about four full adventuring parties.) Grouping in Vanilla WoW also incurs a hefty XP penalty on mob kills, and as I observed when I levelled my paladin on Kronos, Vanilla expects you to actually gain most of your XP through mob kills. Nost leaves you between a rock and a hard place in that regard, as you can group up and kill more mobs, at a pittance of their normal experience value, or try to set out on your own and find most of the landscape already depopulated.
The one amusing exception I found to this were caves. In Vanilla everyone knows them to be death traps, so few people dare to venture all the way into one without grouping up. However, you can then end up in the bizarre situation of multiple groups crowding a cave to such an extent that the spawn timer goes nuts and spawns new mobs almost faster than people can kill the existing ones.
On a more general note, I've also found grouping on Nost to be strangely impersonal. Vanilla has this reputation of being a more social game because grouping is harder and you value your group mates more - and that was certainly my experience on Kronos as well - however Nostalrius' huge population pretty much negates this effect to the point that grouping out in the world feels more akin to the silent dungeon finder groups of modern WoW. You run into an area where people farm mobs, someone quietly throws you an invite because you all know that you're all there for the same reason, you kill things until you're done and then wordlessly leave again - since there is such a high turnover there is no point in engaging in conversation or sticking around.
The one thing that Nost does better than Kronos is group loot, which actually seems to work properly as far as I can tell. On Kronos, at least when I last played there, the loot distribution for the default setting was clearly uneven and not working as it should, and every corpse always sparkled for every group member even if it had nothing on it, which was super annoying.
Anyway, I continue onwards and for now my first big goal is to hit level 18 and start running the Deadmines as much as I can to alleviate those XP gaining issues a bit.