Methos of Aundair said:
I do not feel that not having access to the higher level spells is a penalty to a multiclassed character, that is a choice the player had to make during character creation. If the player sought access to higher level spells (7th-9th) than a pure spellcasting class should have been a more viable option.
Yeah, you trade in high level spell power for something else.
But by lowering your spellcasting class level this way, you obtain three "penalties"... lower spell level (surely the biggest one), lower spells per day and lower caster level.
You listed the Arcane Trickster as an example of how multiclassed spellcasters work fine, if I got you right there. But isn't that what you actually complain about? That there are feats and PrC to increase the capability of multiclassed spellcasters. The Arcane Trickster is one of those. It's purely meant to make the rogue/wizard concepts more viable, as much as the Eldritch Knight makes the fighter/wizard (or sorcerer) concepts more viable and the Mystic Theurge makes the cleric/wizard concepts more viable. And the Practiced Spellcaster feat makes all multiclassed spellcaster concepts more viable.
Of course, it is a very good feat choice for a character like the Arcane Trickster, who is already quite good, as it gives him more choices for spells, which will be useful (offensive spells). Does this make the character overpowered? I don't think so. Having played two Arcane Tricksters from 1st to 19th and 15th level respectively, I think I have a fair share of experience with that class. And I think, that the spellcasting ability is not enough at higher levels without a feat like this. And the Arcane Trickster is surely one of the best PrC for multiclassed spellcasters out there.
For the Mystic Theurge, it's probably even necessary to have him even keep up with a pure cleric or wizard. Mystic Theurge really isn't one of the hottest character concepts out there. We currently have a Mystic Theurge in our campaign, and the character was incredibly weak until now (a lot weaker than the paladin, bard, barbarian, or sorceress). With Practiced Spellcaster, the character suddenly became capable of achieving something, which he was pretty much unable to do so before.
I think that's a good thing.
Tough enough, that he has to spend one of his precious feats to actually get there!
Bye
Thanee
P.S. I also think that the multiclassing rules will have to be changed in 4.0, there is more than enough evidence, that they don't work properly when it comes to spellcasting.