How can you have a balance issue, while playtesting, with a low costing, passive effect magic item? I don't advocate increasing the price HUGELY, like UK might. I simply think the item should cost approximatly twice that of armor enhancement, since, by my arguement, magic combat is at a scale 1/2 of physical combat. A cost something like
+1 2000
+2 8000
+3 18000
+4 32000
+5 50000
Which is the same as the price of an amulet of nat armor.
Or perhaps 4000 for +1.
As for the amulet being as expensive as the ring of deflection, although the item creation rules don't mention, did you ever wonder why Forge Ring gets a feat all by itself? Perhaps because rings are meant to be more powerful than wonderous items. In my homebrew magic creation rules I'm tring to formalize, the ring will eighter be combined with amulets and bracers (one option) or rings will use standard item costs, whereas slotted wonderous items will cost an additional 25%, with ring being prehaps combined with amulet anyways.
For your arguement that because saves are needed, they should be cheaper. Well.. the more valueable something is, the more it costs right? Least that's how it's always worked as far as I can tell, for balance issues.
I mean, look at the costs on any item that gives spell resistance. Spell resistance is a slightly better defence against spells than saves, if you have enough of it, but the items that give it cost outragious amounts of money. The mantle of spell resistance, which grants SR 21, costs 90,000 gp. Since most DMs stipulate that you can spend at most half your money on one item (many say even less), one would need to be level 15 to buy this mantel. SR 21 protects against level 15 spell casters about 25% of the time, assuming no spell penetration. A cloak of resistance also adds about 25% protection. And SR doesn't protect against Supernatural or Extraordinary abilites such as breath weapons, gaze attacks, trap saves, poison, psionics, etc. which the cloak of resistance does help against. There are few spells that offer no save but offer SR, but all supernatural abilites do not offer SR. I've encountered FAR more supernatural attacks than spells without saves. While I'll admit that the mantle of spell resistance is overpriced, I believe that it should cost about the same as a cloak of reistance +5, which I advocate to be 50,000 gp.
As for it being impossible to equal feats to items, why should it be? Both are aspects of character power, they can both be estimated as a character gains in level (because we have a nice chart stipulating the amount of money a character of a given level should have). Therefore, logically, one could equate thier values.
Anyways. I thank you kindly for stopping the excessive use of all caps, which I interpret as shouting. Now we can have a reasonable discussion.
Eldorian Antar