Okay, I got my necro to level 86 and I think I'm retiring him (at least until I've had a chance to get either my zon, sorc, or pally past Hell).
Right now I'm working on a
Hammerdin and he's already doing over 1k damage at level 42. I twinked my character a bit by giving him Milabrega's full set (lvl 17) for the +3 skills and mana/life leech which worked nicely until around level 30. Then I switched to a Suicide Branch (for the FCR and +1 skill), a Steelclash (for the +1 skill), and a rare +1 pally skill helm (temporary, until I can obtain a Peasant crown for the +1 skill). He's doing pretty well with low-level gear. Finally got him up to level 42 last night, so now he can use a HoZ for the +2 skills and +2 to combat, which boosts his Blessed Hammer damage significantly. Pretty pleased by how well he's doing in Nightmare. Just starting Act 2 now, so we'll see how it goes. Normal Baal runs still give good experience, and you can probably do those until about level 47 before the experience slows to a crawl.
This is all on ladder softcore, btw. I was lucky enough to find or trade for these items for my pally, but they are generally easily obtainable.