Support for 'Program All'.
Support for linking both sides while fitting instruments.
Track adjustments history and support Undo/Redo functionality.
Make mute button prominent.
Gain/Vol control with progressive bar.
Drag-n-Drop graph into other side to copy same instrument settings across.
Occlusion management tool.
Feedback management tool.
Real Ear management tool.
Super controls (eg. Bump, Tilt, Gain).