Li Shenron said:
... But this sort of heavy changes are very hard to evaluate balance-wise ... you want to do all of them at the same time

Don't be surprised if it sounds somewhat intimidating to even the regular posters of the house rules forum ...
I think game balance is an illusion. There is just so much stuff out there that nothing can truly be evaluated for balance. Part of the difficulty is synergy. Even in a partial point-system that 3E and 3.5E are using, you can have better or worse combinations. And when a player puts together a particularly good combination of feats and classes, whether deliberately or by chance, is there something out of balance?
The truth is all we can do is not deliberately unbalance things. The rest of it is massaging things into something reasonable that won't break the fun of a game for everyone else in the game group.
In every game, I believe every DM has a sense of what the type of action is supposed to be like. The PHB presents a benchmark that just doesn't work for everybody. The problem comes when you try to force it to work across all campaigns. The idea of Core Classes is just such an attempt. There is nothing "core" about them. Every single character class, core or prestige, carries with it an innate culture--a set of assumptions about what the gaming world will be like. And it all makes sense only if you are willing to go along with that.
You can only break out of that by going pure-point system, IMO (something like using the HERO System, or my own "D10").
The main problem of massive rule changes is the time cost. You're not getting paid to do it.
Part of what makes D&D successful is that it has the illusion of catering to a broad audience, when really it does these things:
(a) Sets a benchmark. What D&D has more or less always done is get people to play the game _their_ way. Whenever you do this, you limit imagination, but you cannot produce sourcebooks that work together without doing this. And if you cannot produce enough material that sells, your company will die.
(b) Uses a shotgun approach. Once it has stabilized the feel of a game, it starts throwing out stuff to see what people are interested in. Then it keeps throwing more of that until people get sick of it.
The idea of Prestige Classes, for example--people want to customize, customize, customize. Why? Because core classes aren't so core. They just don't cut it. Prestige Classes are a great way of releasing the imagination that was held back, while making products that sell. After all, you need such-and-such a sourcebook to tell you what the class progression is, right?
Which isn't as sinister as it sounds: without people telling you these class progressions, you might never have come up with them in the first place. Despite all the activity on the House Rule boards, the mass of the human race lacks initiative and imagination. (Why do you think self-improvement public speakers are so popular?)
Anyway, my free-to-download total conversion project is here:
www.freewebs.com/d20elements if you want to see someone who's restless about D20.
