what points total are you aiming at? 1500? 1750? 2000?
Eldrad + DAs (take 5, drop exarch)+ WS =425
park that infront of:
wraithlord and war walker (would prefer one units of 3 walkers here, rather than the wlord, you could then send the wlord forwards)
with the dark reapers off to the side in cover (but within 6" of the WS).
eldrad can then throw guide on the walkers and either the lord or the reapers depends on which is shooting on a more important target.
drop stones from the walker, and just take 5 straight DRs, no exarch. i dont thinkt he EML is worth it as if you're attacking armour, that's your entire DR units fire 'wasted', and if you leave the exarch with a standard launcher and fastshot, you're paying 32 points for 1 extra shot, which is way too much.
walker, wlord and reapers come in at: 390
you have to take the 5 pathfinders to satisfy the FOC, so that's an extra 120.
total 935 so far.
the harlie group should some in at 226. 7 base harlies = 126, 2 fusion pistolsm TroopM/Seer/Jester upgrades cost 80 and everything up the TroopM (power weapon) and Jester (shrieker) should take a kiss. attaching maugan ra to this unit could be fun, he'll benefit from veil and the unit can throw out 8 s6 shots on the move each turn. maugan also doesnt suck in the assault with his s6 power weapon.
so we're up to 1356
the most obvious next move is to throw in the 2 vipers taking you up to just below 1500. late game you can contest with the vipers and the wave serpent which moves up (with or without eldrad).
if you could find 2 more walkers, then drop the vipers, hide 3 walkers behind the WS collecting cover saves and send the wlord forward behind the harlies (shadowseer is a psyker, so no wraithsight test).
the main problem you have is the majority of your models are shooty, but vulnerable to assaults. deepstriking armies will be hard work. if you could pull together a few jetbikes and maybe drop the vipers and DRs to get the points to field a seer council (fortune seer, 1 embolden lock, rest vanilla) then that might help out. it's a unit your opponents will be worried about, which means he'll be less likely to charge forward and try and tie up your guns in CC.
as general advice i'd make sure you're taking the guns you need for the job you want to do.
e.g. the war walker. you have a star cannon (anti infantry) and an EML (anti tank). eldar is mainly about each unit excelling at a specific task. in this case you have a WS with brightlance for AT, reapers who at s5 can pop rhinos and such as well as tear up infantry. so you're basicly wanting to do 1 of 3 possibilities with your walkers. either 2x EMLs for the anti-tank/anti-horde. 2x scatterlasers which will kill pretty much everything with that many shots (shake av12, kill rhinos, force failed saves on MEQ infantry, thin horde considerably) or 2x star cannons. personally i'd take the dual star cannons. with guide they're pretty awesome and average 7-8 wounds a turn on any armour saving unit. so where the scatter lasers will fail vs termies, the star cannons will rip them apart.
if you're dropping the DRs and vipers to take a jetbike seer council, then you'll need some anti-infantry and both the starcannons and scatterlasers will do that. my prference for starcannons is mainly due to the AP2. no save = kills, and while yes, the opponent will almost certainly fail some saves with twice as many shots from a scatter laser, i prefer certain over almost certain.
NB if you take a jetbike seer council, you'll have to drop maugan from the harlie squad.
so, on the war walkers, which will be largely stationary behind your wave serpent since they can fire over it (if you pick up 2 more and have a squadron then you should be fortuning them too, rerolling cover saves on a fairly flimsy walker = win) where the enemy will be usually coming to you, then taking them out with star cannons is a good way to go. but lets compare that to likely roles for your vipers. they'll be moving fast to collect cover saves, looking to get angles to shoot side/rear armour on transports or tanks. at this point the AP2 of star cannons isnt going to help you at all, as you're attacking armour value units. instead you'd be much better off with the scatter laser as it gives you the extra shots at the same s6, which is all that matters when you're trying to get thru AV 10-11. you're using them to pop the transports so that the star cannon walkers can take the units inside off the table with a turn of fire.
similarly on the wraithlord. if it's hanging back then i'd take anti-tank. makes the most of it's BS4 and put an EML or lance on it (or both!). a lone starcannon and sword wont be much use in a holding role. if it's pushing forward, the sword will be more useful, but it'll become something of a sacrificial unit. it'll draw alot of fire and will go down before the game ends. so a sword/shuri cannon combo isnt a bad choice. you still get to shoot as you're approching (3 s6 shots compared to a scatter lasers 4 is a good return for half the points and the 24" range wont be a problem since you're going to be close to the enemy anyway). since it's going to die, but is a threat pretty much regardless of the gun it has, keeping the cost down with a shuri cannon makes sense.
one other key area to improve would be to improve your troop choices. 5 pathfinders are fine and hard to kill if you can keep the enemy from assaulting them, however they are unlikely to kill anything (ever) and
actually cost quite a few points. for example, 5 come in at 120, while 5 dire avengers in a wave serpent with twinlinked shuriken cannons cost 160. in my view the tank is more versatile than the pathfinders, since you can drop the DAs in cover (and go to ground for a 3+) while the wave serpent moves off to contest in the late game.
