OK Ceres,
In your last post you say that "its when I command a Sharp turn that she rolls". Well if you suddenly apply full rudder (30 degrees or more) to any displacement model traveling at speed then you ought to expect some roll, or heel if you prefer this term.
I see nothing wrong with this characteristic but then my preference is for powerful rudder and throttle controls to get me out of trouble but normally operated with restraint for more realistic appearance.
You still have to describe the models construction in particular the materials used. The reason I ask is that over the years I have encountered some horrendously "over built" models. One example was a modeller who made the superstructure out of solid mahogany, a beautiful wood but almost as dense as the modeller who used it for this application. There have also been funnels made from thick walled steel tubing, which is even denser, material and modeller wise! I'm sure that you do not fall into this category.
Likewise, weighty internal items need to be as low as possible inside the hull. I well remember watching a tug, normally the most safe of subjects to model, which sailed around in a most unstable fashion, even gentle turns had the deck edges awash. On removing the tugs superstructure the large sealed lead/acid battery was seen to have been mounted "upright" rather than laid flat on one side. I guess someone had told this modeller that lead/acid batteries can spill acid and so must be mounted upright?
GlynnG