The view from level 70 is pretty much the same as it was while my Paladin was in his 50's and 60's. There is just literally no fear when leveling a Paladin as retribution. I remember when I was leveling my Death Knight through Hellfire Peninsula, Zangarmarsh, and Terrokar Forest how easy it was to take on elites while solo. Its just as easy, or even more so because you can heal if you absolutely need to, with a Paladin. Even elites that are a couple levels higher than I was at the time were taken down with no problems what so ever.
Anyway, since I last wrote about my Paladin a week ago I slowed down a bit as I slogged through the 50's. Not because of any issue with the class, but because Blizzard never went back and corrected any of the issues pertaining to excess travel required for those levels and because of the lack of quests in any given zone. Vanilla WoW really is horrible compared to the expansions and I really do wish Blizzard would either set aside a few people to spruce things up back there a bit, or start new characters at level 55 like the Death Knight.
Anyway, once I got to about level 55 or 56 I was picking up speed again and blew through levels 58 to 70 over the weekend. Sunday night I hit level 68 and traveled to the Borean Tundra where I hit 70 in just a couple more hours of questing. And that is really where I began to notice a slight decrease in my awesomeness. Again, not related to the class at all, which continued to have all the tools required to get the job done, but because there is a big boost between stats from the Outlands to Northrend.
When I first stepped through the portal to outlands I was at about 900 AP and sported about 3k health. When I traveled to Northrend I was about 1100 AP and about 4500 or 5000 health. Just about three quarters through the quests in Borean tundra I'm already at nearly 1300 AP and over 9000 health. Those kind of stats are found on the creatures in Northrend as well. They hit slightly harder, though I can easily keep up with the damage by healing through it thanks to instant Flashes of Light and Divine Storm, but because the creatures have a lot more health than those found in Outlands it takes a bit longer to kill them. It gives you a feeling of being under powered as you walk into Northrend wearing Outlands greens. Luckily the quest gear you receive in Northrend comes fairly quickly.
By now I've had plenty of experience to compare my Death Knight and my Paladin. Obviously they have different mechanics but I can definitely say that the Paladin has the advantage in survivability while the Death Knight probably has the advantage in burst damage. Overall they offer remarkable similarities in the damage they can take and deal, and their efficiency during leveling. Neither one has any, or extremely minimal, down time enabling hours of questing whereas classes like Warriors, Rogues, or caster classes require certain amount of regeneration time after a few fights.