We can use this topic as a space for suggestions.
Any ideas are welcome!

Just ideas:

-The 'Pan' can be difficult; if other users confirm, a tool&icon could be needed

-Gather the three grey upper icons under 'Settings'(Gear Icon)

-Give a direct access to the languages (as in the TA2 viewer)

-Set a darker grey to the unavailable icons; the 'isolate' icons could even be invisible when nothing is selected

-The 'isolate on layer' could be an option of of 'isolate'

-The function of the icon could be displayed under, or even replace the icon (Select; Isolate; Isolate on Layer; Hide; Frame All/Frame Selected, Cross Section)

-The upper left Cube icon could be simplified (remove the cube) and the 'X', '-X', ... replaced by 'TOP', 'BOTTOM', 'LEFT', 'RIGHT', 'FRONT', 'BACK' or by icons

-Add Hypertext on the names of the anatomical structures inside the definitions to navigate directly from structure to structure.