The spirit stone of Anath'lan is THE single most broken tool the Eldar have these days. All I'm saying is that a single farseer can summon three units of "Ancestor Spirits

" a turn like it's nothing.
So you have a seer council that spawns daemons? gg
Otherwise sanctic has some high end powers to cast, or even runes of fate while rolling for doom and fortune, all have high level powers that would love to be cast for a single success.
If you're taking an Aegis, might I recommend some Dark Reapers with a fast shot Exarch manning an Icarus Lascannon.
I too would drop the fire prisms.. they're too indecisive to be effective.
A spiritseer, with dark reapers and an icarus would make an outstanding backfield addition.