Too Much of a Good Thing

Some games have way more classes than they need.  I mean both base classes and advanced (sometimes called prestige or even paragon) classes.  I understand that players like options.  Options are wonderful things, but not every single idea needs to be expressed by a new set of powers or a new class.
Here is a hypothetical exchange to illustrate my point:
Player: I want to play a Witch Hunter.
GM: No problem; Paladin starts on page 82.
Player: No, I don't want to play a pseudo-cleric-fighter hybrid.  I want to play a character that hunts evil magic users.
GM: What do you think a Witch Hunter should have, classwise?
Player: You know, resistance to magic, dispel magic abilities, powers to smite evil.
GM: I see.  Paladin starts on page 82.

Precisely my 16 year old idea of what a Witch Hunter would be like.

The reason I pick that example is because as a youth playing 2nd edition AD&D that was more or less me.  The player, not the GM.  We had kits back then, which gave special abilities and restrictions to existing classes and there was an Inquistor kit for Paladins that was, pretty much, a witch hunter.  That was not good enough for me for some reason.  Ah, youth.
Some games, and I mean D&D 3rd and Pathfinder, among others, have way too many classes.  Too many core classes when alternate versions are taken into account, too many 3rd party classes, too many prestige classes-just too damn many options.  I say this because every single idea does not need its own special class with special powers.  
Let us say you want to be a monster hunter of some kind.  Perhaps just a monster hunter in general.  What do you think an adventurer does, for the most part?  They fight monsters.  Monsters are those things that litter dungeons and keep you from getting treasure.  Do you need a special monster fighting skill or ability?  Won't your vorpal sword do the trick?
Much of what people want is just window dressing, really.  It is background, not part and parcel to the rules themselves.  Too much specialization can be a bad thing.  Suppose you are just itching to play a pirate.  Does your GM want to run an aquatic adventure?  If the GM is not interested in an aquatic adventure then having a special Pirate Class with special Pirate Abilities is useless to you.
What about a Vampire Hunter?  I've seen those bounce around in games.  We all know the classic vampire weaknesses and a good vampire hunter is loaded with tools like garlic, stakes, holy water, a whip, and a holy symbol.  Yet many a player will expect a special class for that type.  What exactly would such a class have in terms of abilities?  Special undead detection powers?  That's not very vampire hunter.  The ability to hurt the undead and hold them at bay with a holy symbol?  Really all you need are some stakes, a little garlic and the desire to hunt vampires.  Too much specialization means that if there are no vampires to fight you are lacking where a normal base class has utility.  
I'm sure someone might suggest that this is where a classless skill-based game has the advantage, but not really.  Those games either force even more specialization in order to succeed (skill costs) or have special powers with variable costs (arcane backgrounds, for example, to allow spellcasting) that end up making the characters very much like a class-based game character, only more one-dimensional.  I advocate fewer, more generalized classes and then exercising the imagination to fill in the gaps.  Like how we did it in the old days before there was a special ability and skill for every single thing you could possibly do up to and including a skill for writing your name legibly in the snow when you pee.

Player: I want to play a Vampire Hunter.  Somebody that has the powers and conviction to fight the undead!
GM: Cleric starts on page 56.

Keep your pumpkins lit.