I was tinkering with some of my True20 house rules tonight and I had a minor epiphany.
I had been working on adding a 4th role, called the Professional. Like the Expert, the Pro would be mostly skill-focused -- basically an Expert with the Adept's combat bonus. I wanted this role to model fantasy silk-clad merchants or modern era tweed-jacketed bespectacled professors of ancient history or futuristic computer geeks. You know ... guys who wouldn't know which end of a sword to hold or which way to point a gun. To me, the 3/4 level combat bonus of the Expert was still a bit too high for my tastes to model such non-combative characters.
I wracked my brain trying to come up with something to give the Pro that would make it significantly different from the Expert that a player might actually want to take it.
Finally, tonight, I had the DUUUuuuuuhhhhh moment I needed. A 4th role is not required. The Expert fills the role nicely, and all you need to do to make a non-combative Expert is simply to stay on concept
and stick with skill-based and General feats, and not take the Weapon Training feat. The -4 non-proficiency penalty takes care of the non-combative part of it all. Without Weapon Training, the Expert needs to be 7th level in order to have a +1 to hit (not including Dex, of course). I don't need another role to urge character concepts in a certain direction ... True20 as written can do all I need it to do.
All this goes to show me that, more and more, True20 is most definately the system I have been looking for.