Mostly I didn't want to b killed for making Jareth a Baron. The wish lists were so the same it was hard for me to decided who should get what first. (see below)
He might try to kill you if he knew others were controlling events.

But I think it's quite an interesting development.
Is that
another reference to the hydra???
Maybe.

(I can be a pit bull with some things.

)
If it makes you feel better, some monsters really are just too strong for their apparent CR. The critter I mentioned building up a while back got its fight last night... And this monster (Horned Devil advanced to 21 HD and Huge size - CR 20) absolutely mopped the floor with the party. It should have been within their realm of defeating, by the CR numbers, but the rolls made it untouchable, extremely heavy-hitter and all-around death machine. It would've been TPK if I hadn't thrown Plot and Deus Ex Machina at it (realized only after 7 rounds of meat grinder, 3 or so of which it spent out of the fight, tempting and taunting the PCs).
Thanks it was a long process getting all that together and figuring out. Glad you liked it and didn't mind my taking over Jareth like I did.
The little bit you used him for did fit his reactions, so I don't mind.
A pearl of power is prepared only? Odd that.<SNIP>
Maybe they thought in the hands of someone with a lot of spells per day shouldn't have it?
Yep, prepared only. The reasoning may have had to do with the Sor's spell slots, while preparation-casters would expend their battle spells, while having to keep slots filled with utility and buff spells. A Pearl would let them recover one of those battle spells and keep on going.
SRD said:
a potent aid to all spellcasters who prepare spells (clerics, druids, rangers, paladins, and wizards). Once per day on command, a pearl of power enables the possessor to recall any one spell that she had prepared and then cast. The spell is then prepared again, just as if it had not been cast.
Emphasis mine. I agree it was an odd choice to limit it to just them, when it's a Core item. Similarly odd are a number of rules clauses (like Rogue's not being allowed to Sneak Attack if they can't see clearly - shadowy illumination - one of the chief ways Rogue is capable of setting up a Sneak Attack).