When it comes to agonizing over the concept of "which spell to memorize", I tend to forget one simple concept: the magic-user has his spell book with him. When slots are limited, memorize the spell(s) that are most likely to be needed in the thick of things. If a situation arises that requires a more utilitarian spell, such as Knock, or Comprehend Languages, the magic-user can simply "swap out" by studying his spell book. Of course, this does absolutely no good if he has used his available slot(s). Likewise, once the utility spell is memorized and cast, that slot is used for the day. So, the dilemma of when to cast that precious spell remains. . .
I haven't read any of Jack Vance's work. I have certain impressions from quotes and excerpts, though. I'm not sure how "accurate" these impressions are, and I'm not claiming any of this is particularly original or mine, but they are just my thoughts based on the impressions:
Each spell is almost like some alien life form that the magic-user must literally force into his mind. When someone sees a spell without the benefit of Read Magic it can look like anything from mad gibberish, to poetry, to doodles, to a blank page. When read with the benefit of Read Magic, however, it is seen as literally writhing on the page, pulsing and squirming with arcane intent. It is entirely alien to the mind of the caster and his brain must be forced to contain it, forced by sheer effort of will. That is what memorizing a spell is all about.
It isn't easy or pleasant to watch, either. The effects vary with caster level and spell level. The more advanced the caster, and more basic the spell, the less dramatic the process. A 10th level magic-user studying Sleep is hardly noticed. The closer the caster gets to the limit of his abilities, the more dramatic. The process can be downright frightening to behold. "Study" could appear as any of the following:
- Weeping blood as their eyes are forced to take in the eldritch horror;
- Sweating profusely, literally pouring from the magic-user;
- Laughing maniacally and/or speaking gibberish;
- Hair falling out;
- Eyes blackening, as if charred;
- Hair standing on end;
- Grasping his spell book for dear life, eyes opened unnaturally wide, bulging and bloodshot, hair flying back as if a hurricane was issuing from the spell book.
That is just a few ideas off the top of my head as I write this. None of this should have a direct mechanical effect, it is more for dressing. Some of these could have in-play consequences, but they shouldn't become the center point of a session.
All of these realizations have shown me that Vancian magic isn't nearly as limiting or vanilla as I had thought.