Regarding Jeff's comments on this, I look at the evolution of my own magic system and think it's now actually more in the spirit of Vance's Dying Earth novels than the standard so-called "Vancian" system. I still believe that magic is the one part of the D&D rules as written (any edition) that most strongly needs a revamp, in the name of creativity and crazy fun.
* No multiple copies spells memorized ("Turjan pressed into his head ... four Magic Missiles, two Webs and a Fireball in a pear tree.."? I don't think so.) This removes the conflict between pre-memorization and creative use, especially as I'm being more generous with spell slots at 1st level. Perhaps a *different version* of, say, Magic Missile is one of the most prized magical treasures ... but this is as it should be.
* "Push your luck" effects. I am now letting casters try to cast spells above their level, making a difficult Mind save modified by their level vs. the spell's level and any Wisdom modifier (basically, 15 or more on d20). If they fail, they suffer a gnomish mishap. Basically, a more streamlined version of what the DCC RPG (remember that?) was going for. I might also allow the same risky mechanic for multiple castings of the same memorized spell. Magic is danger - not spray-on, EZ-bake sorcery!
This works for me, anyway, and I think my players appreciate it too.