My thoughts on the Mystic Theurge
I feel like I need to put my two cents in here as well, here are my thoughts:
1) The Mth class is overall very boring statistically, lacking anything special other than saying I am a better Clr/ Wiz multiclass combination. The idea though, even a generic one is intriguing, but has not been executed very well.
2) What Monte said about the class is boring to play at first and then comes into its own later, is true. No class should be punished for 3 of its first six levels (ie the required prerequisites of the Mth class) and then become caught up like that.
3) The sheer number of spells that this player has to keep track of is a pain to them, their group and their DM. That is not a fun game design.
4) The real problem here is the multiclassing rules for spell casters. Now a Prestige Class is patching it. That is not a healthy solution for a long-term problem. A player should not look at a multiclass combination of any kind and then be forced into a prestige class to pull that core class combination off. This form of "fixing" only hides the problems and encourages future game material to imitate this sort of game design, which is flawed. What happens as we see Prestige classes that combine all of the classes in some form or another, do we loose the basic classes and just have players playing prestige classes?
5) Mathematically there is a mistake in this class. That is in how its prerequisites are being compared to its level progression. This prestige class itself is not balanced because it is progressing in two caster levels simultaneously. There is no way to making this balanced mathematically. Here is why - whatever you are requiring as a prerequisite up front is your "cost". This cost is going to vary from minor to extreme based on whatever amount of "levels" you require as a cost. The class allows progression in two caster levels at the same time, ultimately devaluing the prerequisite cost unless the cost is to high, in which case the class never comes into its own. The best-case scenario with this class is to have it really fall behind and then it eventually catches up with other classes. Currently this prestige class falls behind 3 levels, then it progresses to much in two levels and causes more and more game complication as it progresses.
6) On that note - why should any form of basic class combination be a prerequisite for a prestige class. If a new player reads the multiclass rules and then looks at this prestige class, the message is that the multiclass rules don't work some of the times. That obviously says - fix the multiclass rules in regards to spell casters. But instead the designers have opted to make a temporary patch that causes another set of problems. In all fairness I understand the complications of what "fixing the multiclassing rules" entails.
A better fix would be a prestige class or series of feats that create synergy between the abilities of a player’s multiple spell casting classes. Overall, I would have to say that the Mystic Theurge is not a very creative approach to the problem and will cause permanent damage in both the fan base and standard of rules if it sees release.
Designers please consider this: I am a player and I want to have a wizard/ druid, cleric/sorcerer, druid/ranger or whatever. The natural tendency is to multiclass core classes together, and then this prestige class tells me that I am making a poor choice in turn forcing me into the prestige class and taking my idea away from me as a player. One thing I know for certain is that Prestige Classes should not do this and they should not over shadow the choice of multiclassing core classes as an option. They are meant to add special abilities, campaign focus or rare rules not meant for 1st level classes onto a character.
Finally I have one more thought for all of you:
Would a prestige class that was obviously superior to any non-casting multiclass combinations (i.e. using rogue, fighter, barbarian or monk) be balanced?
Thank you for listening,
Nate