Atavar said:
The issue of broken fluff is ultimatly a campaign-to-campaign, dm-to-dm one. If you want to examine things from a 'how would they affect the campaign world' standpoint, there are a lot of thing to considder.
Let's start small, for example:
The
Prestidigitation spell completely undermines many of the service industries as well as spice trades.
And that's just a cantrip.
Another?
The presence of divine magic confirms faith. Theocratic government would be the standard rule because you
know that they have God on their side. Improper judgements can and would be sidestepped via use of Augury, Divination, and Commune spells. A popular church-body would be an unstoppable jugernaut and inexpliciably tied in on all levels of society.
Another?
The bardic abilities
Fascinate and
Suggestion would lead to an inherrant distrust of musicians and public speakers period, because if you listen to them they can control your mind.
Another?
There is no Elf-Orc animosity because if there was ever a war, the elves would all die out due to the long lifespan and accompaningly slow birth rates. Elves would make damn sure to stay out of the way of any shorter-lived, faster-breeding races because if there's ever a conflict, the elves just can't keep up in the numbers game.
One could go on and on endlessly about these things if they wanted to. Ultimatly you either factor them in to your game, or you choose to ignore them.
As for the Incantifer's fluff being broken from an in-game perspective? Take those prohibitive exp and gold costs, the rarity of the training, and then ask yourself just how many of these guys are there? Enough to have any functional impact on the game as a whole? No. No more than a lich or elan. Heck, a lich would be worse because in addition to them being ageless, you can't kill them permanantly. And it's easier to become a lich, to boot.
Ultimatly it's not that bad. It's just another chit in the pile. In the end I'd say it's less broken from an in-game fluff perspective than many other aspects that have been long standing pillars of the genre, and never seem to get analyzed in this same fashion. Forest for the trees.