If every spell was given a point-cost based on it's level(lets keep it simple, we've got 10 levels, each spell costs the amount of points from the level it's in) I think it would go a long way to making the Vancian system much less confusing. Metamagic feats would increase point costs, moving spells up "spells levels" to power them up would increase point costs, same with moving them down. Say, 2 points per level, and one extra point per level based on your int/wis/cha mod. If we keep the DDN style of capping at 20, then by 20th level a player has at best roughly 140 points to spend. While that seems like a lot, if a 10th level spell costs 10 points, that's only 14 spells, which should be able to be completely spent in a 20th level encounter.
I dunno, the Vancian system as it has been in D&D has always bothered the heck out of me because it seems to convoluted for no apparent benefit.
Points-based casting flat-out doesn't work with D&D spells if you use a linear cost, the reason being that spell levels do not increase linearly. A
gate spell is not worth nine
sleep spells. Spell power is closer to exponential (i.e. a spell of level X is roughly equal to 2 spells of level X-1). If you want to do a points-based system with those costs, a 9th level spell would cost 256 spell points--possibly less if you try to flatten the curve by deciding that spell power doubles every two levels instead of every one, for instance, but certainly nowhere near 9.
The reason 3.5 psionics works relatively well with points is that the powers are designed with the assumption of points built in, so you can spend more points on each power to scale them, and psionics is generally less powerful than magic, but it still doesn't work very well because non-numerical stuff still doesn't scale well. It's easy to decide that 1 PP = 1d6 damage or 1 PP = +1/3 AC, because the basic numerical stuff is easy and the first thing people think of, but is being able to cast two spells per round for 1 round/level (
schism) worth 7d6 damage? Only at the first level you get it, and only if you're only spending 1 PP per round; after that it's worth a lot more, because you can generate up to [level] points' worth of extra effects per round for up to [level] rounds, which is 7*7=49 points when you first get it. That's a lot closer to the theoretical exponential cost of 64 than 7 is.
Spells don't scale linearly, and that's partly what slots are for: you can't trade in all your low-level spells for an extra high-level spell. Slots also mitigate nova-ing, dumping all of your spells as fast as you can; a 20th-level psion can manifest about 28 9th-level powers before he's out for the day, while a 20th-level wizard can cast at minimum 40 spells of 1st and higher, likely closer to 60. Slots enforce creativity to some extent, because once you're out of your big guns you have to determine how to overcome obstacles using lower-level spells. There are plenty of other benefits to slots (less math, easier by-round calculations, etc.) but those are the big ones.
That said, there needs to be a range outside this optimum - low levels for the character and story buildup, and high for the rest of the world to use.
The best and easiest way to extend the sweet spot in play is to make each level take much, much, MUCH longer to get through than has become the modern norm.
Some of us like playing at the high levels, actually, so I'd obviously prefer that they make the high levels work for the players too, thank you very much.
One of the reasons I like D&D is precisely the fact that you can get to those high levels and start shaping the world, unlike say Shadowrun, Riddle of Steel, or even d20 variants like Iron Heroes. Most of my campaigns have made it to at least 18th level in both 2e and 3e, and my group enjoys the Logistics & Dragons aspects of high-level play.
WotC assuming that no one plays high levels is precisely why 3e starts to fall apart around 15th; they playtested the low- and mid-levels but ignored the higher levels. Could high levels have worked if they hadn't ignored them, and might the Epic Level Handbook not have been a joke if they actually understood how high levels differed from low levels? We'll never know, of course, but the fact that 3e works all the way up to 15th-16th while AD&D started to lag around 12th shows that high levels
can be made to work without turning them into "low levels with bigger numbers" if you actually try.
But then you have to put it into the perspective of game design. And here you have plenty of interconnected issues to keep in mind, for example (a) how "granular" you want the character advancement to be, (b) how well you can separate spell effects in a vertical hierarchy, (c) how much difference you want to allow in characters of the same class e.g. in term of spells known, (d) how much space in the book can you allocate for a number of spells, and certainly more.
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Overall it becomes a serious design restriction. I'd rather change the name "spell level" to something else than restrict design this way.
Precisely this. Gygax had a section in the 1e DMG describing why he used "level" for so many different things (basically, because trying to come up with separate terms sounded a bit hokey), but the independence of spell level from character level can be important for spell design.
First of all, having fewer, broader spell levels allows you to have spells that blur the boundaries. If you have one spell level per character level, you have to determine what a 6th level spell is and what a 7th level spell is, and you run the risk of having spells that are a bit too good for 6th but not quite good enough for 7th; if you use the 9-level scheme, you can make that a 4th level spell and allow yourself a bit of leeway, and that only becomes more important the more character levels and the fewer spell levels you have.
Second, fewer spell levels allows a better distinction between them. As was noted earlier, each spell level has a different "theme" of sorts: 3th level is the "AoE effects" level, with
lightning bolt,
explosive runes,
sleet storm,
daylight,
major image, etc., 5th level is the "long-distance effects" level with
teleport,
lesser planar binding,
sending, etc. If you split those further, the spell levels lose some of their identity.
Third, leveling spells allows re-use. One of the big complaints about 4e was that so many powers were redundant between classes when they could have just written one "roll your key stat vs. AC, deal 2[W] + secondary stat" (or whatever) power and allowed multiple classes access to it. Same with spells: the various casters in AD&D/3e are defined as much by the spells they share as by the spells they don't. It allows more character options if you can make roughly the same summoner with both cleric and wizard (they share most summoning spells with minor differences, so class doesn't matter for that schtick and you can customize in other ways), if you can make variations on a necromancer theme with different classes (the cleric does minions better while the wizard does SoDs/debuffs better, but both can do a bit of either), and so forth.
You can also re-use spells at different levels. If you can make a single spell different levels for different classes (such as
plane shift being 5th for clerics and 7th for wizards) you can give access to the same effects but give the classes different strengths (e.g. clerics can access the Outer Planes before wizards can, but can't teleport within the same plane like wizards can without the right domains).
The issue is not the number of spell levels. The issue is how many styles of play can ONE game try to support without resulting in inadequately supporting all of them in order to make all styles work within those same ruels? I'd be much more sanguine with an attempt to produce three entirely separate sets of game rules for D&D (gritty, heroic, epic) than producing one set of game rules which supposedly does it all.
D&D has never really done "gritty" at all at low levels. Lethal, sure, and detail-oriented, but not gritty; that's the domain of hit locations, persistent wounds, and so forth. D&D actually does a fairly good job of retaining the same gameplay at different level ranges while changing scope and feel compared to other games: you're leading hirelings through kobold warrens and hoarding
expeditious retreat spells for quick escape at 1st and leading armies through the Abyss and hoarding
plane shift spells for quick escape at 12th, but you're still dealing with party-based tactics, minion control, resource allocation, attrition combat, and such at every level.
The difference between the various level ranges is one of degree of plot control. There's no need to write entirely new sets of rules when the difference between "mortal" and "heroic" is that in the former case you find out about a demonic assassin by hearing rumors and chase him by finding a portal to the Abyss and in the latter case you find out about him with divinations and chase him by plane shifting. Combat certainly changes from a straightforward "chuck firepower at it until it dies" contest to maneuvering around layers of defenses, but that change works because the underlying system
is the same; again, it's a matter of degree (a single
mage armor at 1st level vs. layers of magic items and resistances at high levels), not fundamental difference.