Chaplain Swordwind Rating:
Durability: 2 of 2
When I originally math-hammered this, I came up with an estimated 1.5 out of 2, but considering all the tactics you use to preserve your forces (Reserves, dual Fortune, etc.) it earned the full 2 points. In your hands I see most people having significant trouble inflicting casualties against this army.
Flexibility: 2 of 2
My ONLY concern was the fact that you have only a single close combat unit, but considering that unit is to absurdly tough, its more or less the equivalent of 2 other close combat units. The way this list is put together I suspect that you wouldn't need any backup for the counil at this point limit anyway. When you do bump up to 2500 points, I agree with your choice of Striking Scorpions.
Lethality: 1.5 of 2
This list will bring the pain. However, it is geared heavily towards self-preservation, rather than the all-out destruction of the opponent. Units like the Defender Guardians and the Dire Avengers are clearly not intended for offensive operations, so the list is not quite as destructive as it could possibly be. I'm sure the damage output will be more than adequate for your purposes though.
Mobility: 1.5 out of 2
Mobility is a significant asset for this army. It might seem odd that this list does not receive full credit when everything is mounted in fast skimmers, but considering that the Seer Council needs to be in hand to hand to fufill their purpose, and the amount of points invested in that unit, 1.5 is what you end up with. If your Serpents had Star Engines, you'd definitely score the full two points, but that would require compromises elsewhere that would probably reduce the overall effectiveness of the list.
I am aware that Eldrad's Divination allows you to redeploy units, thus potentiall allowing your council to get where they are needed that much quicker; but I factor that particular ability into other parts of my evaluation, like Flexibility and Synergy.
Synergy: 2 of 2
The whole of this army is greater than the sum of its parts. Though you seem to have restricted yourself from using certain units in order to remain within your theme, I do not believe that has hurt this army in any way. As a whole, this list is incredible, and in your experience hands, I expect that most people will have a hell of a time finding a solution to it.
Total: 9 of 10
This is the highest rating I've ever given to an army. It just seems to have the right blend of everything, and when you factor in the amazing paint job on your models, your history of good sportsmanship, and your experience as a player, this really looks like the best army I've ever seen; a "sure" tournament winner (as sure as any army could be anyway).