Alright so while I was having a run on train of thought I ended up putting several things together for this suggestion.

First off, one of the reasons one might be fighting a evil/rival/opposing spell caster is you want something from his spell book. It would be interesting if the developers would actually make it so that there was a fairly decent chance upon killing a named spell caster that you could get something from his or her spell book. This could add much to otherwise drab quests. Especially if they were to give out spell variations from the named casters that one could not get any other way.

Which brings me to my second point, named spell variations. This would dramatically give wizards a boost. Upon acquiring the scroll for a "unique spell" that cannot be learned upon level up the wizard can scribe it into their spell book and have it until they either re-roll or true reincarnate. A sorcerer would have to take that scroll to their trainer and pay to swap a spell to learn it. And if they ever replaced the spell variation they would have to hunt down that scroll to learn it again. Meaning wizards have additional situational spells at their disposal quickly while a sorcerer really does have a sacrifice to get them or replace them. Additionally this would be a great way of injecting new named items into old locations.

And finally the lack of named loot that appeals to everybody drags down a number of adventure packs and free quests. By introducing named content that is not bound to character, but is nonetheless a potential must have item that there will always be demand for you create a reason to actually aquire said packs or run the under utilized quest. I'll give a few examples here.

Thyp's Emerald Lances
As per the Frost Lance spell only its 4d8 Acid damage per lance. A simple re-work and yet it gives an under-powered element something useful.
Location it could appear is in Acid Wit. Said quest has no named items and the acidstone elementals on higher difficulties almost require a spellcaster to eliminate in a timely manner. Having a named spell would give spell casters an incentive to actually run this quest with parties.

Trassilyk's Tainted Elemental
You know those acidstone elementals? Be neat if we could actually USE one now and then ourselves. Again Acid Wit, would probably be a fairly high level Summon Monster spell equivalent (either 7th or 8th... most likely 8th) An elemental that has added acid damage on hit, can land CON damage on its hits as well, etc. What is there not to like? I'd probably run the quest to ransack on a weekly basis until I got this spell. Either that or pay a small fortune on the AH.

Sinvala's Breath
As per the Cone of Cold spell, only its now a 6th level spell doing acid damage.
Have it potentially show up in the additional warded chests that only unlock upon Sinvala's death in Mired in Kobolds. Other than the small chance of getting a black dragon scale there is almost NO reason to spend the time to kill her. Most groups anymore merely kill the small dragon, speed loot the chests and run away. This would give a pretty good reason to stick around. Besides killing an adult dragon usually is for something in its hoard isn't it?

Mak-Murug's Elemental Call
As per the Summon Monster V spell, only instead of an Earth Elemental its a Fire Elemental.
The Stones Run Red in Three Barrel Cove, you know that adventure pack that has in all honesty no named items you can take home and keep? Yeah something like this could be a real incentive.

Ahraatz-Ri's Elemental Binding
As per a Summon Monster spell (probably 6th), only this one gives us control of one of those new water elementals. Neat new content, and the fact that they have an aura that puts out firewalls is interesting. Especially if one could summon one up while playing through the desert where there are all those firewall happy arcane skeletons. Location being one of the chests at the end of The Tide Turns, because frankly that little eternal wand is kind of a joke for arcanes at an appropriate level to run the quest on say elite. Great item to hand to a new alt, not so great for your 9+ wizard or sorc who lands sucker punches with Cone of Cold already.

Rowan Watzun's (insert spellname here)
Turbine is introducing new necromancy spells in update 5 right? Take one of them as appropriate and make it a little more powerful. Bump it up a spell level if needed to keep it balanced. Would be neat to actually get a spell a would-be Pale Master would maybe want from a Necromancer NPC. Location obviously being Spies In The House.

Plenty more that could be thought of and implemented. As usual comments and ideas are welcome.