Currently, the default layout has AudioSpectrum and Spectrogram in separately docked panels. IMO, that makes the layout too wide for a suitable default. Audio Signal is also, but that is more commonplace and probably justifiable. Also, with all of the scopes enabled by default and placed onto the panel together with Effect List and Undo History, it can be argued it forces that panel to be too wide.
-- +-DRD-+
