Many people have brought up the idea of creating [Prestige] feats that give you some of the benefits of a PrC (with limits; I was thinking of making mine all [Superlative]* feats plus a restriction of a max of one PrC). IMO that might be a better idea since you can control prerequisites and whatnot, but I guess for certain types of PrCs it wouldn't hurt to make them base classes.
Granted, I'm hesitant to make too many base classes because that means I have to make up capstone feats for all of them, but that's not a balance issue

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*For those of you who haven't seen my idea of [Superlative] feats, they're basically feats with a base prerequisite of 15 feats. After taking a [Superlative] feat, the prerequisite for all [Superlative] feats increases by 10, although you can't lose the benefits of a [Superlative] feat due to this increased prerequisite. Basically, they're a way to (a) make feat-based races/classes more attractive, and (b) allow me to create more powerful feats with a way to limit how many can be taken.
There are also reasons to think that E6 is less prone to catastrophic unbalancing than d20 (i.e. problems don't get multiplied over 20 levels, there's less power leverage, and less story-shaking magic).
Definitely agreed. However, from my point of view, E6 offers a unique opportunity to balance the game since the cap is much lower and there are fewer wrinkles. And I like game balance, so I'll seize the opportunity

. And I've had enough with Monks sucking

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