GW really needs to revise there codex's.
Whoever wrote the eldar codex is a dumbass. Everything in eldar is weak besides Wraithlords, Fortune, and the Aspects. That basically means that every cheesy Eldar army is Biel-Tann, because every eldar player plays Biel-Tan.
If whoever wrote the Eldar codex actually wanted some balance, they would have made guardians like they used to be in 2nd Ed, made Wraithlords a bit more expensive, made Wraithguard, Jetbikes, Shining Spears, Rangers, Avatars, Shuriken Cannons and Scatterlasers cheaper or better, we would have a much better codex that is more balanced.
Really, I believe that every new army gets better and better, and therefore is called cheesy.
Also, I encounter people that should be slapped in the face for calling things cheesy... I was playing 40k in a Flash (500pts. downscaled) and played a Khorne army with a Daemonprince, Defiler, and two min squads of Zerkers, he called a necron army cheesy because it had 3 wraiths split up in squads of 1 each. Things like that ruin the game just because its rediculuos. Daemon Princes are great lords of war and huge battles and they somehow get assigned to a patrol? Same with Defilers....
One thing to make the game alot ALOT less cheesy is to put point restricions on HQs, Elites, Fast Attacks (maby, they are already weak as hell) and Heavys. This would make real, fluffy battles instead of who can buff the demon prince better.