Start of Rant:
Why on earth do you make so many of your methods and fields private as opposed to protected?
The ones you do mark as protected are often unable to be overridden because too many calls they make are private as well. Driving me Crazy.
One example of many:
I'd like to override the ResizeTool's behavior so that when the Control key is held down, it preserves the Aspect ratio of nodes regardless of the EditStyle.AspectRatio setting. This would require ONE line of code if I could override your "GetNodeAspectRatio" method (it's private). Instead I have to override the entire HandleMouseMove and write all the hundreds of lines of code and methods below it.
Crazy.
IMHO, nearly all, if not, every single method and field of a commercial library should be protected, not private. Either that or mark everything private and don't allow any overrides.
Doing so would take your code from good to great.
End of Rant.
