alt Hacker NewsI have not tried building custom solutions in Blender, but Maya is built for custom solutions. The entire thing is a C++ engine and then the UI you see is built from scripts, scripts you can fork and edit. (or it was as I haven't actually used Maya in a while). And of course they there are plenty of examples of customizations or custom UIs included to help get started.
Note: Blender might have this too. I haven't tried. But, my impression so far is Blender didn't start this way and trying to add it in after the fact is difficult. Maya stays clean because any UI feature needs to buildable from scripts. By enforcing that rule on themselves, they keep it customizable.
oh yeah i remember how maya was architectured so well, and from the start indeed. i don't know the innards of blender but the python layer seems powerful.. yet afaik there's no derived computed attributes like $ball.x = $feet.x / 2 or that would require using some 2nd class objects (transformators or something like this), quite un-ergonomic.