I've had some (great) experience with Jython, working on layouts with NodeBox for exemple.
It would allow to solve so many tricky, silly ... features that one may desire and you devs will never provide, because the dude is the only one who requests this apparently silly stuff ... that he seriously desperately needs inside YED ! Maybe because YED is so cool , and he became kind of addict ...
It would provide many solutions to data binding that Excel + Property Mapper doesn't always solve easely.
Again, thanks for the great tool ! I discovered it inside Class Dependency Analyzer : wow !
Best regards, Stan