The problem is that improvements for you would not necesseraly be improvements for others, for example, the daz studio interface is quite different from poser but I still find it quite awkward to use.

Please point out which of my examples would not be an improvement, and for whom this would be the case.

There's something to be said for taste, but there's a limit to the argument and Poser is way beyond that limit.  No, sorry, there's no argument to be made for putting all those finger joints in the list, or having right-click do nothing, or having the top border of the scene pane take up almost an inch of screen space, 90% of which is empty and serves no purpose.