Alzrius Casters don't run out of spells after about level 5. If you're playing a caster in a way that does, then you're playing it wrong. I don't know how you can continue to believe they do, especially when even Wizards can get up to 8+ spells per spell level and carry an effectively infinite number of wands.
I honestly wouldn't even recognize a game played like this as being D&D. Spellcasters absolutely run out of spells above and beyond level 5. My 8th-level spellcasters did in last night's game, across seven encounters altogether.
I'm not sure if you're looking at some magic items (
rings of wizardry, perhaps?) that allow for more spells per day, but on bonus slots via high ability scores, eight or more spells of each spell level per day (for a wizard) is, quite simply, insane. I'm sure there's some sort of CharOp build for it, but there's a CharOp build for Pun-Pun too, which is my way of saying I don't find such material to (as I've said before) be very relevant at the game table. I won't even mention the idea of an infinite number of wands.
Likewise, if you're going to say "if you're not doing it min-maxed, you're doing it wrong," then there's going to be very little left to discuss. I'm trying to say that such theorizing about power-builds doesn't mesh with actual game-play; to say that means the game is being played wrong is to take the idea of the game over the game itself, and I can't believe that anyone would do that.
Played correctly, you never "have to choose" to use a "big gun", you can fairly well perform the same function every encounter, all day.
Blasting is not the role of the caster. I make no claim that Wizards and Fighters can deal the same amount of damage all day - the fact that an optimized Fighter can deal (under the correct circumstances) hundreds of damage per round with very little chance of missing is the only role he can actually best a caster in.
See above for my response to "played correctly" versus "played incorrectly." It's an ironic truism that only bad players tell others that they're having BadWrongFun.
Likewise, I've already spoken to the idea that wizards are always better than fighters because wizards can control the entire battlefield. That's only true under hypothetical scenarios which are designed specifically to support such a position.
Regarding the rest of the text on Pg. 49, no one stopped reading. In all of those cases, you're still expending the same amount of resources per day - about 80%. If your caster is blowing his load early in the day, he's being foolish - like an archer using all of his arrows, a fighter using all of his potions, or a rogue throwing all of his grenades.
In the case of low-ECL encounters, one spell can take care of the entire encounter. One Grease (even if you save, you move at half speed) can give your party the time to take them out with ranged attacks, spending less than 5% of your party's resources. One Darkness gives your melee fighters with Blindfight/Blindsense time to kill everything without getting hit - again, less than 5% of your party's resources.
This is more theorizing that ignores how things actually play out - the little details that somehow never make it into these scenarios - when you sit down and actually play the game.
Grease, for example, covers a 10-ft. square, so you're always adjacent to the edge of it. It's one easy check to move out of the area, and so eats up five, maybe ten feet of the enemies' movement...presuming they aren't flying, that it isn't an aquatic area, that they don't just do around it, or jump over it, or burrow under it, etc. The idea that "you can destroy a lower-level encounter with a single spell" is a myth that doesn't exist outside of the aforementioned theory-crafters' pet scenarios.
Regarding "single standard action replacing party member" - lets say you cast Summon Monster I and bring out a Celestial Dog. That Dog can effectively replace your Fighter for the duration of the spell at lower levels. You get a full round action, they get a full round action. The Medium Centipede can best a Fighter, considering the 1d3/1d3 Dex damage.
Again, this doesn't hold up to closer scrutiny. Even leaving aside the incredibly short duration of this spell, and that the spellcaster needs a full round (not just a full-round action) to cast it, a celestial dog has 6 hit points, which means that even a first-level fighter has it beat in terms of lasting in combat (not that it can anyway, with it's poor duration). It's also one
protection from good away from being unable to attack a given foe.
The idea that a summoned monster can simply replace the party fighter outright is, quite simply, misguided unless you're looking at a very specific scenario for very specific parameters for a very short period of time.
Grease removes the Fighter from play by making it move at half speed or fall prone.
Untrue. See above.
Fly forces the Fighter to twiddle his thumbs while you do whatever you want to him.
Ranged weaponry. Magic items. The list here goes on and on.
Regarding taking his weapon to prevent tripping - without his weapon, he doesn't threaten nearly as many squares, reducing his ability to control a battlefield.
If we're talking about tripping, then without his non-reach weapon, he can still trip just as many possible squares as he could before. If you're referring to making trip attacks of opportunity, that's as easy as Improved Unarmed Strike or even a spiked gauntlet.
Regarding Reduce Person - It lowers his To Hit, his Damage, and his reach - since you're wearing Mage Armor or Bracers regardless of the presence of Fighters, your point is moot.
You're not making sense here. A Medium-sized fighter reduced to Small-size has the same reach as he did before. Likewise, my point from before was that the overall difference from better armor (hitting less of the time for average damage) versus a damage penalty (hitting an average amount of time for less damage) being equalized on a scale wasn't moot - you simply didn't understand that it's a way of showing how damage penalties are no more effective than a higher AC.
Regarding "if you take away this, he'll just do this" - Fighters are forced to specialize. Trippers are generally not Damage Dealers or Grapplers. Grapplers aren't Trippers or Damage Dealers. Damage Dealers are not Grapplers or Trippers. Taking away what they are good at forces them to do something subpar, like removing the Rogue's ability to Sneak Attack or the Archer's ability to stay at range.
See, this is where the theory-crafting goes completely off the rails. Characters aren't "forced to specialize" in anything except very broad terms (e.g. multiclassing can make it harder to excel in a given area). A fighter that has a trip weapon and Improved Trip can
still hit things for damage.
Regarding "lol saves/rolls" - use spells that target weak saves. If your opponent has a high AC, hit his touch ac. If he has a high touch, hit his square. If he has a high fort, hit his reflex or will. If his Dex is high, hit another ability score. No one has all around perfect defenses, there is always a hole that is easy to ascertain.
Leaving aside the "easy to ascertain" bit (which is another way of saying that you'll have metagame knowledge about what opponents you're facing), this still presumes that you have a perfect choice of spells available and that the dice will go your way much more often than not. I've been trying to tell you for a while now that this isn't always so, and quite a few times it's only rarely so.