Some interesting feedback, thanks guys.
Regarding the EMLs, I have not had the bad experience that you all seem to have had. I consider them to be primarily for popping transports so that the Wraithguard units can shoot and assault whatever was inside. The Wave Serpents are, after all, only a taxi service for the Wraithguard and anything they do beyond that is a bonus. I use the Wave Serpents as a pack, making good use of the 30" move in the first turn. The death-dealing begins proper on turn 2.
The Heavy Weapon Platforms are quite useful, and can be hidden in a far and safe corner to provide cover fire for the initial Wave Serpent rush, and the Rangers are usually ignored because the Wraithguard that are only an inch from the enemy's face generally present a more urgent target. That means the Rangers can cap, and snipe to their heart's content in relative safety.
In my last game I tabled a Dark Angel army on turn 5, with the loss of only one unit of Wraithguard and the Wraithlord. The EMLs were perfect in their appointed role.
All that is important is known.