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1 Autarch: fusion, mandi, pw, warp jump
10 Warp spiders: exarch with power blades, deathspinner x2, withdraw
1 Autarch: fusion, lance, mandi, bike
5 Spears: exarch with starlance, skilled rider, withdraw
10 Banshees: exarch with executioner
1 serpant: BL, stones
3 War walkers: scatters
1 Falcon: BL, stones, holo
10 guardians: EML, warlock with conseal, Seer, spear
10 guardians: EML, warlock with conseal, spear
Wraithlord, BL, EML
Preaty simple. Spears and spiders try to pincer individual units in cc, attempting to wipe um out in one round. Tougher targets that cant be eliminated that quickly get the banshees. Autarchs are mobile and can split off to do some solo tank hunting if needed. Warwalkers outflank in and assist the cc units in wipeing them out. Falcon is a fire base as well as an objective getter. guardians and lord make up my static fireing line in the back, with the lord providing counter assult. I considered 6 harlies in place of the lord and in the falcon, but figured the lord is both a nice fire base, and a good fire magnet. While all my scary stuff is on their side of the board, my lord will still interest them on mine.
With your short points get another DA and make him an exarch.
Always place your spears and warp spiders as close to the edge of your deployment zone closest to the enemy, always take turn 1, always assault on the first turn.
keep your autarchs and friends in reserve.
Eldar -APOC- 6500 Points
Chaos Daemons -Fate Crusher- 3500 Points
Grey knights - 1000 Points
Your list seems very good, it is very balance but the one problem i see is your lack of mobile armor. Yes, you have the falcon and War walkers but one falcon is not enough and the War Walkers are very slow. But I do like the wraithlord for this list, it usually does not fit in with lists like this but a bullet magnet fits very well.
In my opinion(you can choose to do this or not, my opinion is not law) I would add another Falcon and some anti-tank instead of your war walkers. Fire Dragons are very good anti-tanks i use them in my list.
As i said before these are suggestions not law, but a very good list despite the flaws i see.