I've always been annoyed at the fact that there are no randomly generated (oldschool gold) staffs or wands with inspiration requirement in Prophecies (or Factions for that matter). Looking into it, it appears that the same is true for heal and prot. And then there is blood which has no exclusive skin but can still get a ghostly/shadow/dead/raven staff with blood req, and curses which has a staff but no wand. Summarised:
DF is a primary attribute with special status (the only one in the list of possibilities for hsr/hct/mastery mods), so a DF weapon with mixed attribute is still useful. However, mesmers have simply no way of focussing on inspiration. Why would anet create the attribute only to neglect it?
I would like to hear some theories about why there is no support for using inspiration in Prophecies. The first thing you think of might be that "inspiration was intended to assist all casters as a low-level attribute instead of being a main focus attribute'", but then why leave the mesmer with only 2 main attributes when the others have 3-4?