As I've previously detailed, the thing I love most about Third Edition D&D is its amazing flexibility and elegance. A PC of any race can take any class, any feat, any skill, and at each character level, you can pick a level from any class, or take a level from many prestige classes. The elegance is that the rules to do so are both easy and balanced; it's as easy to make a cleric 3 / wizard 3 / mystic theurge 10 / thaumaturgist 4 as to make a fighter 20.
That flexibility -- the power to create a character a la carte, with a level here, a few more there -- is remarkable and empowering for players. The game promises ultimate flexibility and, to a degree, delivers.
In large measure, I have not moved to the new Fourth Edition of the rules because they are a departure from this philosophy. (For the record, a few of my other problems include the influence of minis and MMORPGs on the rules and flavor; the anti-open-content attitude, itself also a departure from 3E; the (mis)treatment of alignment; and the way that all classes basically perform the same mechanistically, just with different flavor text for each.)
But in practice, even Third Edition does not live up to the promise of complete balance and ease of use. So I have been toying with ways to improve upon 3E. One option might be to rework all the core classes -- and I still may do so. Or I could create all new classes from scratch, and I decided to try that.
By way of background, years and years ago, Clinton R. Nixon, a game developer, was running an online game magazine called RPG Evolution, if memory serves. There I read a set of rules for running very small creatures (mice, rats, etc) as players in a game called "Vermin." It was open source under the d20 license, so I feel free to be inspired by it. I found a copy of it on the Wayback Machine, and I still love the concept. So I'm going to remake Vermin in my own image.
First off, I'm not going to call it Vermin, since that's a game term in 3E that refers to giant insects and other invertebrates. So I came up with and considered a few other options. "Small Fry" is too cutsey. "Bugs," too limiting. Hey! rather than a noun, how about a verb? "Scurry" works kind of well -- that'll serve as a working title.
So what sets Scurry off from standard 3.5 D&D? Here are a few highlights:
1) Smooth, fractional progression of saves and attacks with level.
2) No special boost when you take first level in a class.
3) Every level delivers something useful; no one level offers much more than another,
4) Multi-class casters are more balanced in power with single-class casters.
5) Feat and ability score boosts progress evenly.