Interesting to me is that the Drakon editor was implemented in Tcl/Tk, a language I'm quite familiar with. I regard Tcl as a dialect of Lisp, which I've also used a fair amount, at least in the guise of Scheme.
As I'm not at all familiar with this new language can't say too much about it, though implementation in Lisp might be a plus. One issue with it, as with other efforts in this domain, may be that it's not as intuitive or obvious as its authors believe. IOW, in my admittedly limited experience with visual programming, there's more of a learning curve than advertised.
Visual "syntax" is sufficiently different from conventional text-based forms that people have learned to use, often at the cost of great effort and time. Translating the thought process to a visual metaphor isn't intuitive or easy as I've attempted to learn it.
What's odd is that I have ability and a fair amount of success in the visual art of printmaking, which one could say is an expression of a visual language itself, but one that doesn't map well at all to the visual coding of computer programs. No reason to think it necessarily would, but the observation points to an apparent multiplicity of "visual modes" embedded in our brains.