As I said, if we assume there are very few spellcasters, that makes the spells much more mysterious. But it also begs the question how the wizard (or anyone else) finds exactly the spells and items he wants, when he wants and has the gold for them.
He researches and masters the formulas/gestures etc in his downtime at the tavern (or his pocket dimension or his own study), while on watch duty, between adventures etc. He creates the magic items with Scribe Scroll and the various Craft feats. That was the narrative crux of what my Wizards did. I thought that was the conventional justification/M.O. for Wizard progression through levels?
Why is there such a ready market if no one can identify them, make use of them, etc.?
I never assumed there is a "ready market". That is an implicit setting assumption you're making that I'm again disputing.
Why is it so easy to locate weird spell components?
This is a bit of a granular resource tracking and process simulation issue that never comes up in my games. I've never hammered Fighters for encumbrance, I've never hammered Rangers with harsh accounting of arrows, and I've never hammered Wizards for spell components. By my way of seeing it, its just a 3.x flavor issue, not a balance issue of 4th level spell versus 4th level spell. If i had to oversee the accounting for spell components of the level 11 + Wizards in my 3.x games (with 9 kajillion spells), I would have seppukued long ago and wouldn't be writing this post.
As far as just a setting justification issue? Off-screen, downtime brokering, collection in oddities, antiquity stores and harvesting themselves. I'm not going to spend time onscreen going potty and not going to spend time onscreen while the Wizard goes shop to shop or explores local caves looking for bat guano and grinds things to dust with his mortar and pestle. Pretty sure my players wouldn't enjoy that.
And how do PC's have such standard knowledge of magical abilities if they are rare in the extreme?
I'm not really sure what you're talking about here rules-wise. If you're talking about players at the table (not characters) using metagame information to make decisions then the answer is quite simple; the players are using metagame information to make decisions for their character.
In general, if you're referring to adventurers having arcana or spellcraft etc, then I would just say:
1 - That is the hybridized narrative/metagame construct of classes.
2 - That metagame portion provides what is needed for functional play. That narrative portion presupposes a career of adventuring requires an entry-level understanding/exposure to magic and perpetuates a post-graduate (from not having a class to having a class) education with respect to the requirements of the job...which entail dealing with and handling magic.
Layfolk don't have classes and aren't adventurers/Big Damn Heroes who brave crypts full of Wights et al for Flaming Swords and Invisibility Cloaks. They till their land, cobble shoes, barter for daily/seasonal supplies and hope their wife/child survives birth. Or they attend balls, drink the finest wine, cavort with the opposite sex, learn the newest dances, and partake of the newest fads. If they're stupidly filthy rich they might be able to hire a low-level Wizard for parlor tricks etc. But all of these are setting issues. It can be whatever you want it to be.
For that matter, how did all those unbeatable mages if the past fail to rule the world? Why aren't elves and liches in charge?
Again, setting issue. This will vary by group. However, if FR is anything near the bog standard implied setting then it is fair to say that elves and liches are "in charge". That is to say if "in charge" means they are in charge of the most powerful empires in the world (Netheril, Thay, Evereska, etc).
Seems like a dissatisfaction that the wizard is not simply allowed to be omnipotent. The Forgotten Realms you use as an example seem pretty chock-full of spellcasters, in my experience. If there's a ready market for magic items, I'd expect some public awareness of them, and I'd expect planners and tacticians to consider those abilities. It seems like "magic is dripping from the trees" is very popular when the spellcaster wants a scroll of a specific 5th or 6th level spell (or a gross of Cure Light Wounds wands), but not so popular when the ramifications stop working entirely in their favour.
I don't think that is fair. I've always considered one of my most important roles as GM is to maintain an empathic link with my various players. Be considerate of what they want out of this game. I don't think its unfair at all for a Wizard player to create a rules-legitimate build (even a bog standard one) and expect me to impartially adjudicate play...not use metagame concerns to consistently, adversarially strategize the entirety of my world, my conflicts, and the scenes I frame around what he can conceptually deploy to solve those conflicts, to re-frame those scenes. I can easily, easily, easily destroy any Wizard by doing this. I can do the same thing with any aspect of my game. So I beat him to the punch (or I cheat on the fly when he has pressed the win button), Wizard-proof much of my world/conflicts through fiat, and render inert his archetype/build...what exactly have I gained besides an unhappy player?
As far as the rest of it goes, I addressed it above. Magic doesn't hae to be dripping from trees for Wizards to have their spell gain per level, their scrolls and their wands. They research them, they spend default features to create them and they invest in feats to create the rest. There is no double standard here. You can have few mages and a lot of magic items if there is enough time to accrue. There are lots of castles in Europe and no one is in the business of creating castles these days. There is an enormous, vast, unbelievable swath of TSR products out there and nary a TSRian producing them in the last generation.
Since every one of them has Blindsense, why would they be motivated to waste a feat on it?[/QUOTE]
I still don't know why Blindsense is coming up. 60 ft isn't in the same universe as the range of Spectral Hand. Its useless versus Spectral Hand. Can we turn the page on that one? Regardless of everything else, assume the Wizard doesn't do all the Divination and infiltration tricks to get in Spectral Hand range of the Dragon. Lets assume the group does it. Now we have this epic fight with the dragon right? This climactic fight to end this tier of play! The Fighter and Cleric charge forward to engage for a titanic clash of elemental forces that is sure to ring out in song and legend for ages to come...except Spectral Hand buffed before fight, Assay Spell Resistance as Swift Action and Shivering Touch the dragon to 0 Dex with an SR check that is impossible to fail and no Saving Throw. Fight over.
Again, the things that make Wizards game-changers are their abiltiies to compel, divine, explore, travel through space and time, transmute, and bring into existence that which didn't exist. Not slay dragons with Spectral Hand, Assay Spell Resistance, Shivering Touch.
And one final note on high magic implied settings with Wizards everywhere. If Wizards were everywhere the world wouldn't resemble anything that the current implied setting does. There would be fresh water and food till the end of time, no one would have to work with undead and construct minions, teleportation circles would make flight and rail of our current era look archaic, and an economy based on Fabricate would never want for materials. It just doesn't fit.