I think that it's time that the antiquated editor in FPSC was replaced with something more intuitive and on par with other game engines. And this does not hav to be written from scratch. Here is an open source 3D world editor built on the irrlicht engine that could be taken and modified to use the FPSC renderer and features.
http://www.ambiera.com/irredit/downloads.html
If you download the irrEdit version you'll see the basic code you get to start with. Then if you look at the latest CopperCube version, you'll see what others have done by building off of this open source code. The CopperCube version is nicer to work with and has a very intuitive workflow.
I think that FPSCR could adapt this kind of editor by replacing the render system with their own and have a far better editor for game developers to work with.
If this isn't the route that is best then I would still highly encourage the implementation of features such as scene hierarchies, property panes, transform widgets, layers, etc.
System Specs: OS - Windows 7 Home Premium 64-bit SP1, CPU - AMD Phenom II X4 945, 3.0Ghz, RAM - 8Gb DDR3, GFX Card - 2048MB NVIDIA GeForce GT 640, FPSC-R Version - Beta 1.006
