I only brought Eldar for my anti-air needs before. Now that I can get razorwings in FA, I might not need to do that. I'd still like the autarch for reserve manipulation, but I can see me just grabbing a bunker or aegis with comms to control my reserves. Yes, there are lots of fun combos I can do with Eldar stuff, but I also see plenty of stuff I want to fit in from the DE and Covens books that I think I can cover all my needs with.
Even with ideas like deepstriking wraithguard, you could just use medusae instead. Firedragons tempt me, but with the new scourges it won't be much different than bringing a couple of those units down as I please and it will keep my hq from feeling wasted as a support for the eldar.