LokiDR said:
The goals of EK and Spellsword are the same: make a poor multiclass option into a decent option. The difference is that Spellsword is weak but nifty. EK is on par, but boring. Those two attempts should be brought together to create an interesting and effective combination.
I don't know the Spellsword well, so I won't comment on its power level. If it's over-weak, it should obviously be brought up-to-par.
I will speak to the role of PrC's in general: They are supposed to add a flavourful, interesting role to the game (ideally one which is codified in the game
world), which can not be trivially reproduced through standard multiclassing. If a PrC happens to overlap
slightly with a multiclassing niche, that's supposed to be coincidence, and the PrC should occupy a narrower role.
Thus, no, the Spellsword is not supposed to prop up a poor multiclass option.
The EK is not a good PrC, because it is not designed to do the things that a PrC does. Instead, it is supposed to serve as a systems patch for a failed multiclassing role.
As such, the EK fails in its duty, the less generic and more flavourful that it gets.
If you want fighter wizard with nothing else, multiclass. It doesn't make you an effective character, but that is what you want.
No, what I want is an effective Fighter/Wizard. Not an "effective member of a particular order of martial magic users from the Southwest corner of D'ran who use the philosophical beliefs about their ancestor spirits as the cornerstone to their fighting style," a frikkin' effective Fighter/Wizard. Period. End of story. Why is that so difficult for you to grasp?
I acknowledge that some GM's, of course, feel that Fighter/Wizard
shouldn't be an effective multiclass, but I'm not playing with them. I'm playing in a game that sees no reason why it shouldn't be just as reasonable a choice, with tradeoffs and ups and downs, for a Fighter level 7 to take his next level as a Fighter, as a Rogue, or as a Wizard, or for a Rogue 2/Sorcerer 2 to take his next level as Fighter, Rogue, or Sorcerer.
"Normal" Prestige classes, with idiosyncratic style and flavor, may or may not have a place in my game, but they do NOT fill the role of patching multiclassing. Multiclassing patches should be as generic as multiclassing, because
that's what they're trying to replace.
Now. I actually would go with a different clunky, lame patch (a variant of the one that Will mentioned), rather than the Eldritch Knight/Mystic Theurge/Arcane Trickster patch that 3.5 presents, because for all that the "virtual spellcasting levels" are a clunky, lame patch, they're a more versatile one than the "generic PrC's patch."
But none of that means that the generic PrC's "ought" to be regular PrC's.