I think there are options here, but the strategy behind how you use the Iyanden is key and possibly needs more thought than for other armies. I have posted
some thoughts here because someone else has asked exactly the same question.
I might add that Rangers become a key formation on OW to protect the SS against exactly the kind of sneaky Marine trick pointed out by Tim
I still think that a pair of SS may also be sensible, because even if one is destroyed the formation can break forwards to allow the other gate to be used. Indeed, a formation of three SS puts your BTS in hams way somewhere near the enemy and this probably mandates the use of an even larger Wraith formation, which in turn puts a huge drain on points. Though at 5000 points and with appropriate supporting formations, it might just be fun to try
However, as things stand at the moment the Iyanden list tends to present narrow strategic options with all eggs in one basket and no 'plan B', which makes for increasingly binary results; you either win or lose big. While I have always found the Eldar to work best using a single theme in a given game, at the moment things seem overly restrictive.