Roll shouldn't be substantially different. The things I changed were that I found that it didn't have enough dihedral, too much prop mass, and I increased the effect of the rear fuselage on directional stability.
Thanks for the details Pyro, they are always interesting to hear! The dihedral didn't come to my mind but the other issues were something I was suspecting.
Had to relearn combat trim of course.
I'm not sure if I understood this correctly or not. Do you mean that you had to "teach" the combat trim function to account for the changes you made to the model? Anyways, very interesting.

Regarding the rollrate,
Considering the limited data out there when it comes to the Brewster's roll rate, I don't really have any "issues" with the roll rate. I might cross test it with the previous version just to see if I'm imagining the change.

Other than that the roll rate is fine, it could well be that it was "too good" previously and that it is now more realistic, who knows...or it might not be changed at all and that it's all in my head.

Stoney,
Just for interest, Brewster's dihedral is 5,5 degrees. No idea how much Pyro had to change it.