Well, the issue is it went from being an abuse of power to being a direct mapping of substance abuse.

-- all indications that she was misusing magic, and showing a lack of judgment with the power.

But if they'd run with that, I think it would have been a lot better. They laid the groundwork for Willow pushing boundaries, beginning to cross ethical lines - but it wasn't about the magic, it was about the result.

all indications that she was misusing magic, and showing a lack of judgment with the power.

Misuse, yes, addiction--no. Making it an addiction problem gives her an out, whereas being irresponsible and power-hungry are character issues that have interesting connotations.

Making it an addiction problem gives her an out, whereas being irresponsible and power-hungry are character issues that have interesting connotations.

that's an interesting thought, although I'm not sure that addiction is really an "out', they just made it seem that way. Like when people miraculously quit drugging/drinking when someone ODs.

all indications that she was misusing magic, and showing a lack of judgment with the power

What the others have said. There weren't any warnings that magic was addictive, as opposed to a power that could be abused.

The point where I was expecting some sort of magical backlash was in the episode where Buffy went back to see the first Watchers. Willow's trying to open a portal, and when the spell isn't working she just calls up raw power and demands that the powers obey her. I thought, "Honey, the universe does not appreciate being ordered around." I was surprised there wasn't some mystic backlash.

Again, the addiction angle didn't bother me so much as how it was handled. People having withdrawal shakes, getting back-alley magical hits and breaking into houses to steal sage were all just over the top and ridiculous. However, I agree it should have been setup much earlier if that was the route they were going to take, rather than the abuse of power angle they were doing up until that point.

just fixing Smashed and Wrecked would completely change the character of the entire Willow/Tara thing,

If I remember right, Smashed presents it as a power trip rather than... the other kind of trip. I liked that episode when it aired, which made Wrecked's awfulness that much more shocking.

One could say that Mutant Enemy was addicted to the power of allegory, leading to the car crash that was Wrecked. I mean, it starts out all right-- slaying the demons of high school; finding out your boyfriend is a monster-- but then you're making spells the equivalent of lesbian experimentation, parodying other shark jumps by inserting actual family members out of thin air-- and we know the rest.

breaking into houses to steal sage were all just over the top and ridiculous.

although it would have been really funny to watch some housewife making a nice pork roast be set upon in the kitchen by a sage junkie.