By the same logic, spellcasting classes are vastly more powerful for the cost than full Bab classes, so it's stupid to choose full bab classes.
I get your point, but the fact that the game has imbalances is not an excuse to add an additional imbalance.
Again, go check all the awesome magic options rangers and paladins get in splats.
You've mentioned those. I don't think they're as powerful as pure metal. Let's put it this way: If you were forced to play a ranger from level 1-20 in your system, would you even consider picking magic items over pure metal? This isn't a leading question -- it's just something you should think through. At the very least, it will help you balance the items for your own system.
Any low-level character or NPC class: No. You can get hugely powerful items for 2gp with pure metal, while the cheapest magic weapon costs a thousand times that.
Maybe now someone will care about NPCs other than the Adept then.
You missed part of this, which admittedly was only implied: Even a level 1 wizard is probably better off wielding a pure metal crossbow. Even adding a +500 or +1000gp cost to these items would fix that problem, without getting rid of the balance you're looking for.
You're almost making it sound like monks were playable before. You ever noticed they're tecnically not proficient with their own unarmed strikes?
This is getting off topic, but I've always thought that's a silly argument against monks. Not listing unarmed strike among the monk's proficiencies was an obvious mistake. It could even have been omitted deliberately, so as not to insult the intelligence of the reader. Who would ever read the Monk description and think they weren't proficient with unarmed strike? The answer is, only someone specifically setting out to degrade the monk.
In fact, monks actually are playable, though they have many flaws. In a lower-power campaign, they can be quite fun, especially at lower levels. In a high-power campaign, they have to be multiclass to be competitive, but 1, 2 or 3 levels are still worthwhile (3 to qualify for Psionic Fist). I played a monk-like character (2 levels of monk, focused on unarmed strike) for 25 levels or so without feeling like I was the weakest member of the party. But back on topic...
Look, if you want to convince me, you better start showing me some solid number comparisations instead of random values.
Ok. Pure Iron Dagger. Cost=2gp.
Powers:
* One size category higher. This is similar to Improved Natural Attack. Some feats are priced at 25,000gp, so let's start with that.
* Don't miss on a 1. Hard to price. It's effectively +5% damage if you hit often, or less if you don't.
* Add BaB to damage: Anything from +4 to +20 damage. Again, not sure how to price this. 20 damage is almost the equivalent of 6d6 though, which, on a magic weapon, would cost at least 72,000gp.
* Critical threat increased by 1-5. Unknown price.
* Ignores miss chances on a 20. Unknown price.
* Can crit elementals. Unknown price.
If you say each unknown factor is worth 5000gp (which seems low for some of them), you're getting at item worth roughly 117,000gp for 2gp.
Pure Iron Chain Shirt plus heavy steel shield. Cost=120gp.
Powers:
* Hardness 3 (effectively DR 3/-): You can get this from adamantine armor, so let's price it at 9000gp or so.
* +3 touch AC: Worth about 9000gp
* Add half BaB to AC twice, plus 2: At level 20, this is +22 AC. which would be priced as an epic item at 4.84 million gp. However, this is a non-standard bonus type, which would probably double that cost to 9.68 million.
And these are some of the cheapest items with the weakest powers that pure metal offers.
What can a warrior with just pure metal items do against a forcecage?
Disable the caster beforehand, which is quite easy with pure metal.
Or a Gate spell?
Use his superior equipment to fight whatever monster comes through, or better yet, kill the caster easily first so he can't cast a second gate spell.
Or if the spellcaster is just floating in the air, invisible while messing up the weather to make it impossible for you to shoot or move by yourself while raining down destruction on you?
How did I get into this situation? I should have disabled the caster before he cast all these spells.
Have you ever seen a self-buffed druid/cleric's combat numbers?
You don't have to convince me that spellcasters are overpowered. This is why, in the midst of all my criticism, I keep complementing you on the overall feel and structure of your system. It does a great job of balancing mundanes and casters. It just has a few balance issues of its own.
Don't argue like spellcasters are just walking around unbuffed and just throwing unpimped magic missiles and fireballs.
I did play with someone like that once. Even worse, he would often cast no spells at all, and use his single level of Eldrich Knight as an excuse to break out his non-magical sword.
I just realized one more thing, which might have been a mistake on your part: You say you can change the radius of the AMF at will, with Artifactwork Cold Iron armor. This means you could change the radius to 0', and be permanently immune to all magic.