OK, I've been playing Eldar since the days when there were only pirates and Harlequins (all hail the backpack grenade launcher full of Vortex grenades!!!). I can't claim to be the best player, but I do have lots of xp and have won more than lost.
1st things 1st...Dire Avengers and Guardians! You need at least 1 10-man squad of DAs with an exarch with Bladestorm. Kit him out otherwise as you wish. I would leave them out of a wave serpent unless you have a specific and purposeful reason to do otherwise.
Guardians should be at least 10-man strong (Warlock w/Conceal if you like) and Star Cannon platform. It moves, it shoots, it kills jarheads d-e-d! They're fairly cheap, fairly reliable, and claim area.
I would say lose the Wraithguard until you are ready to field 2000 pts. I really want to use them (and always have) but I have to believe those large points are better spent elsewhere
Put the Banshees in a wave serpent! Make them a full 10-babe squad...more attacks is always better is HtH!
Take the Dragons out of a wave serpent, make them 6 strong and put them in a Falcon. You don't need more snakes than that to do the job and the Falcon is some kinda good
Oh yeah, I second the idea of rangers or pathfinders...either one would be an excellent 4th troop choice if you have the room
Last observation, I really hate the starcannon/brightlance mix on the Wraithlord. I know, I know...twin-link sux when you don't want it, but it really seems pointless. Either decide it's gonna kill jarheads and light armor, or kill heavy armor...trying to mix both together is gonna waste you shots and points that are better spent elsewhere...like that Falcon maybe!
I know I'm being a smart alek, but I hope this does help you out bunches and good luck! May the wind be at your back and the mon-keigh under your thumb!!!