I have been thinking, a bit facetiously, about the disconnect between Vancian magic in older systems of Dungeons and Dragons to the more unlimited "power" based approach of magic in 4th edition. It seems that wizards, or to generalize any class from the "arcane" power source, got a considerable leg up, especially at lower levels, with 4th edition. Besides just shrugging and making any number of arguments about why 4th edition breaks D&D or is an MMO on paper, the disconnect between earlier edition wizards and 4th can, potentially, be put to good story use in-game. I must admit that the inspiriation comes partially from Terry Pratchett's Discworld novels, specifically the wizards (wizzards?) at Unseen University in Ankh-Morpork.
Chiefly, what if Vancian magic is just a theory? Like, in the D&D universe, what if wizards traditionally were able to only cast one spell a day because that's just what they were taught? This assumes that wizards undergo magical training at some sort of wizard school, which is well within the bounds of the theory about wizards generally. One also can easily harken to Jonathan Strange and Mr. Norrell, with Mr. Norrell being representative, by and large, of the Vancian theory. Magic should be properly respected, especially by younger, more inexperienced, wizards, and so it is not only improper but potentially dangerous for an inexperienced wizard to go wild with Magic Missile before he truly understands the arcane energy that he is summoning together in order to coalesce it into the force commonly referred to as a Magic Missile. Additionally, by casting it once a day a wizard can be certain that he will have assumed all of the proper concentration and focus necessary to ensure that it will land and have an effect.
4th edition, by contrast, is a much more free wheeling, damn-the-consequences theory of magical practice, and as a result of that, is less effective. The compromise for breaking in to the arcane energies faster than with the Traditionalist school is that, quite often, magic can come off only partially formed, and fizzle out midair rather than land its target. A missed die roll in 4e represents a failure to summon together the proper arcane forces and is not so much an abject failure on the count of the wizard himself, but a consequence of trying to do too much, too fast, which is largely representative of this school of magic to begin with.
One can almost assume that earlier editions of D&D took place in an earlier, more chaotic time in the collective D&D'verse's history, and, as time went on, not only did the world change, but the ideas of the people in the world changed as well, and part and parcel to that, one can certainly expect a paradigm shift in magical theory. The older, more cautious Vancian approach is almost entirely subsumed beneath the newer, flashier 4e system that allows for such (in the eyes of the Old Guard) unnecessary ostentatious displays as "Jim's Magic Missile."
In game terms I see absolutely no reason why a player, even in 4th edition, couldn't create an "old style" wizard who still insisted on making the tradeoff from having At-Will powers to having spells have a much more definite chance of hitting. Whether this is practical or simply stubbornness, it doesn't ultimately mechanically matter. Perhaps take a page from the Dungeon Crawl Classics RPG and have powers that are usually At-Will not be expended if they miss, but have powers branded Encounter or Daily powers continue to get the Vancian treatment. There would almost necessarily have to be some power creep involved in the powers themselves, to counterbalance the more limited expression they'd take with this system in 4e, breaking the balance of the game. But I don't think that's necessarily a bad thing. How this would look in Epic level though, I have no idea. Perhaps it might be worth, at level one, awarding the Vancian "Old Guard" wizard one additional feat in order to trade off for the power imbalance.
One of the things I really appreciate about the Dungeon Crawl Classics RPG is that it makes dabbling in the arcane arts extremely dangerous. While DCC might go a little overboard with it, the lesson is still there. Vancian magic shows a bit of respect for the forces that are behind what makes magic "work," which is something that completely disappears from 4e. Magic becomes frivolous and carefree, which not only loses its flavor compared to other similar-leveled powers from other classes, but also makes it ultimately less interesting to play a wizard as opposed to another arcane class that might deal more damage, like a sorcerer. Adding a little more danger, or uncertainty, or even flavor in this way might be the solution to the otherwise uninspiring wizard. If anyone tries this out, let me know how it works.