So far in the past 2 weeks, i've played twice Dark Elf, both time using Death Magic against me. there's not much that can be done against Purple sun except, maybe, let everything pass but this spell... i've lost 12 bulls in a single pass, and 8 IG in another.
Small units can help reduce the high death tool of those spells, but i dont think anything under 6 Bulls/IG will stand much chance against DE. After all, your chance is in the 2nd round of combat, when their wounds inflicted start to go down.
If he does not go for Death, Shadow is even worst. MindRazor can reduce any unit to dust in a single round of combat. I'm personally an abuser of that spell when i play my Dark Elf, so believe me, it can beat any units without any problem. It's another spell very important to keep dispel scroll for (and of course, dispel dice).
Overall, i think our best defense against DE, is to maximize our magic phase, so they MUST try and dispel some of our buff in their round of magic. If they are forced to do that, you have much more chance to reduce their offensive spells. No DE want to fight Ogres with regen (well, except when an hydra breath is nearby, but that one only breath at Ini 2, and against that one unit with Fire banner).
Scraplauncher is a very nice way to reduce the usual lvl4 mage bunker (also known as Power Dice Pool). 2 for maximum chance of reducing it quickly.
that's pretty much what i've come to expect when facing DE.