I think the defense could work if played right, but it might be a bit spread out. Set Fire and Seven Sons can stay, but I don't see the value in Flying Flames or the crimson Panic Demon.
If your opponent attacks with Gabriel and has half of a brain, however, your offense dies (but you probably realized that). I would say that if you want a small offense and huge defense, you should go with a Chamber/I am Holy/at least three Angels strategy. That also allows you to take out 3Nails, which has the doubly bad effect of taking up Blindness' spot and stopping your demons.
I'd really like to see a viable Blindness defense work though, and I think you might be on the right track.
