The Inkscape stroke dialog is what I prefer to call a Palette and it is intened to be always left open and is deliberately compact.
The GIMP uses a transient dialog which is quite different and follows the GNOME HIG rules for layout of that kind of dialog. This is a perfectly valid approach and for GIMP users. I dont think the stroke options are so important that they need a palette always open taking up space onscreen.
It begs the question does inkscape need a Palette rather than a standard transient dialog?