It would be interesting to see the list (or at least types) of programs you use that require Windows. I've got a CAD program that I've been using forever that does (TurboCAD) and I'm more facile in Corel Draw than Inkscape (which is horribly, horribly under-performing on the same hardware booted into Ubuntu 12.10).
Does Corel Draw use some kind of graphics hardware acceleration (e.g. Direct2D)? I find that GTK software completely ignores hardware accelerated rendering most of the time; Cairo (which renders most of the GNOME UI now) is pretty much completely a software renderer, and the GNOME 3 desktop only uses OpenGL for window compositing, not most drawing, as far as I'm aware.