So far my Drakkin necro is level 10, with around 5 or 6 hours played; for comparison, that is exactly the same as for the same levels in WoW.
I could have reached level 5 easily in either Gloomingdeep, or Crescent Reach. But you really need the tutorial zone (Gloomingdeep) to get the Kobold Skull Charm; and, as a Drakkin, at level 5 you can get your breath weapon from your dragon. To do this, you should take only the quest from your matching council member; the other quests give you 1pp, but nothing else. You then get a quest to kill a rare spawn (oh, memories!) in the Hollows – which is a decent levelling area for 5-10, the other side of the town in Crescent Reach. The spider you have to kill is about level 8 and is moderately tough for the level – meaning that, untwinked you may just be able to kill her solo at the same level.
As you reach level 10, you can kill your way around the mines easily, only needing to be particularly careful for the various bosses (Ruga and his guards, etc). At that level, the higher areas in the Hollows are still too high except in a group, and the top floor of the city is a reasonable levelling area. The boss there, Charbones, drops his skull for the second breath quest.
As a necro, my choice of the black dragon wasn’t the best (his breath is disease based; fire or magic would have been better; disease works better for a shaman or beastlord).
One thing is puzzling me – I heard that there was a potion belt, to make using potioons less painful (they have to be in top level slots to click otherwise); unless that was part of the Ro expansion, which I don’t have, I can’t find it.
The various change to out of combat regen, potions, and so on aren’t all that big: unless your entire world has been Everquest, of course. You still may need to sit for a few minutes to regain full mana and hit points, even at level 10; it is just a few less minutes. Easy availability of damage shield and regen potions for newbies makes powerlevelling available to everyone, and on every server, not just where you have higher characters. That does have some compensating advantages and levels the playing field some.