Victim said:
With high bonuses, +skill items overwhelm the character's innate abilities. I think that this problem is especially pronounced with skills because usually no other factors besides the skill bonus come into play.
I couldn't agree more.
Powerful skill items allow for untrained characters to perform amazing feats, and for trained characters to have incredible opposed checks - unless of course the enemy also has +skill items. Quite frankly, I don't think we need another area for characters to have a magical arms race.
I agree.
This is a bit off topic, but in my game, I ruled that A) characters need to have 1/2 the bonus of the item in ranks, as per boots of elvenkind and B) an item can't more than double your existing skill bonus. A guy with +6 tumble who puts on the belt of acrobatics +30 only gets +6 from the item.
Interesting. I wouldn't use the limit of "the item can only grant as much as you have" for my game, because no other item works that way, but it's neat. The fix for skill-items in my game is:
1) Item creator must have as many caster levels as the bonus to provide (+20 skill item takes 20th-level spellcaster to make)
2) Item creature must HAVE as many ranks as the bonus will provide or use a piece of a creature with as many ranks as the bonus will provide. (+20 to Hide skill item requires the cooperation of a character with 20 ranks of Hide)
3) Cost increases to bonus squared times 200 gp.
(thus, a +5 item is 5,000 gp, a +10 is 20,000 gp, a +15 is 45,000 gp and a +20 is 80,000 gp). This reduces the "arms race" issue and makes them valuable items rather than obnoxious freebies ("oooh, for 2,000 gold I'll add +10 to my move silently with boots of elvenkind. Sure, that's more useful than a +1 dagger!")
4) Item increments are typically +5 and typically not higher than +20.
5) Like all items, I may give a +100% to cost for obnoxiously-useful skills in combat (tumble, concentration, hide, spot). This I haven't decided for sure.