It would be nice if more of the windows were undockable from within the program so you lessen up the clutter and put what ever window you wanted on a second monitor. Now I think there are only two windows that are undockable from the program.
I can’t speak for the dual display set up on Windows as our windows TBS workstation in the studio is a single display. But I can tell you that the Mac workstation we have is a dual display and Toon Boom on the Mac is really flexible in terms of panel placement. -JK
A simple but but not so neat solution would be to configure your desktop as a single surface the program would be spread across. For example, instead of having two separate 1200 X 900 work areas, you would have a single 2400 x 900 area. This assumes you have same sized monitors set to the same resolution side by side to avoid going crazy. You could organize the TB work area by putting the timeline on one and the sceneplanning/drawing view on the other.