Well, in game terms it could work that way, but in the novel it looks more like an actual Death Curse. Harry uses up all of his regular magic, but he's so angry that he reaches further and his body begins to shut down on him. Sounds pretty Death Curse-like to me.

Also something to keep in mind is free will. I would argue that only a practitioner who has free will can cast a death curse. We get into a grey area with vampires as they seem to be creatures with far more free will than other monsters, but less than humans. Vampires aside though, most monsters shouldn't get a death curse. Faeries, old gods, dragons and the like are all bound by rules and limitation that might not be readily apparent, but forbid them from taking actions of true free will and thus cannot act outside of those restrictions. further, it is entirely possible that most of the power they wield are mantles of one form or another and the power of a mantle can't simply be used up and discarded, it must be passed to another individual (as logic would dictate by the very nature of a mantle of power).

Harry does almost kill himself with magic a few times in the book, just when he is slinging it around at his enemies. It's entirely possible if you don't stop yourself in time you could bleed yourself dry with magic, possibly with one big spell.

1.  In my experience, it's not specializations that create a problem, it's Foci.  Remove the accuracy bonus that control foci give but keep specializations.  Remember that a +3 bonus to 1 single element represents 3.5- 4 refresh...If my math is correct.  That's a big investment for a single weapon.  The problem with Foci is 3 refresh represents +6 accuracy since foci don't need to stick to a pyramid.

2. I don't understand 2.  Please elaborate.

4.  Instead of removing weapon values, why not just give them a base?  Like weapon 3.  So they act like any other weapon.  You can still add power to make them zone-wide and stuff.  You could have some kind of algorithm that increases it. Where it gets more and more expensive the higher you boost damage. like 3+*2 weapon damage.
So 4 damage = 3+1*2= 5 Power
5 damage =3+2*2=7 Power
6 damage =3+3*2=9
- I'm just throwing around numbers...doubling the Power for each point of weapon damage is an easy fix (#5)  10 shifts for weapon 5.  and the math is easy. 

4.  This is interesting.  Accuracy is always better, though.  I'd rather hit with a weapon 2 than miss with a weapon 10.
let's assume Power 5; accuracy 5.
I'd always put 3-4 shifts into accuracy.  Now all my attacks hit because I'm starting at +8-9 accuracy.  I don't really like the idea of a sliding scale for accuracy.  It puts way too much control into the casters hands....especially since every point of accuracy is a point of damage anyways.

Look at it this way:  I roll a 5; weapon 5 attack.  Opponent dodges with a 4.  I do 6 damage: weapon 5+1.

Or I put 4 power into accuracy, weapon 1.  Opponent dodges with a 4.  I do 6 damage: weapon 1+5.

same damage but the latter method ensures that I ALWAYS hit.

I'm not sure why it puts a focus on maneuvers....

But yeah, keeping track of passive skills is difficult as a GM, at least it is for me.  I like to hope my players will call it out and make up for my failing in that area.

I think you misunderstood me.  I said attacks can almost always be dodge by athletics.  I can see maneuvers targeting specific skills.  But not only.

The problem is evocation, generally, targets athletics.  It's only, really, Thaumaturgy that let's you target a specific skill.  There's exception, I suppose, and it probably depends on your GM, but for the most part you can dodge any evocation with athletics.  And any evocation that targets discipline has problems with Lawbreaking.

"Blinded' aspect.  Resisted by alertness or athletics.

I'd say that's more of a declaration tagged for effect to allow you a perception roll to overcome the veil.  Success means you can attack them.

The problem is evocation, generally, targets athletics.  It's only, really, Thaumaturgy that let's you target a specific skill.  There's exception, I suppose, and it probably depends on your GM, but for the most part you can dodge any evocation with athletics.  And any evocation that targets discipline has problems with Lawbreaking.