@Zagorath I look for items the players need and for items that are thematic! Anything else matters very little! Certain mundane things could be useful, but magical items are generally more fun! Oh, and if you're willing to balance your encounters for things like "the party refuses to get any kind of armour rune because there are cooler magical items in the magical shop", then it really shouldn't matter too much!
@Zagorath I look for items the players need and for items that are thematic! Anything else matters very little! Certain mundane things could be useful, but magical items are generally more fun! Oh, and if you're willing to balance your encounters for things like "the party refuses to get any kind of armour rune because there are cooler magical items in the magical shop", then it really shouldn't matter too much!