It could also be that your souls suck
When I played Necromancer during Beta, I used Necro/Warlock/Chloromancer. This gave me amazing survivability, what with Radiant Spores helping to heal my pet, an instant heal in case of emergencies, and Life Leech. Your soul choices seem to make very little sense to me.
-Why Elementalist, first of all. 2/3 of Elemental Link don't help, since you use undead pets, not elemental ones. The crit is nice, but most of your spells are DoTs.
-Why Dominator? Is it just for transmo? I can understand that... but your point choices are all over in this build. You don't max out any talents, making me feel like you just wanted the armor and reflect abilities and didn't actually care much about the talents.
-Some of your talent choices in Necromancer seem lackluster. 1/3 Detonate Bones? You want to keep your pet alive, so this talent has little use. Consumption would be much better, as it un-buffs an enemy while restoring your mp. Or Grave Rot, an AoE that also gives a full stack of Deathly Calling on all enemies who stay in it. Ancient Tomb probably isn't needed since you'll never use a rogue pet solo.
Next issue are the pets themselves. If you're not using the tank pet, you can't really complain about "pets suck at tanking." I think this might be exactly what you're doing because you say "pets." Use the Knight and that's all (I think it's the Knight, might be Stalwart? Whatever isn't capped at 30).
Final issue is how you're fighting enemies. Necromancer is not a sprinter - it's a marathon runner (aka, sustained damage instead of burst). They kill more slowly, but they can kill literally without any need for rest indefinitely. They can also take on 2 enemies at a time constantly - send you pet at one and tank another yourself, healing with soul purge + essence link + radiant spores + leech life. I never had an issue while leveling to 30 except for when I took 4+ enemies (usually because I had adds show up).
I could be wrong. Perhaps Necromancer is completely different at 43 than at 30. But it really seems like your soul, talent, playstyle and pet choices may be to blame, not the class itself. Edited, Mar 16th 2011 9:13am by LockeColeMA