This is exactly why most 'visual programming languages' don't take off - because they fixate on a single means of repreaentation - which will never cover all use cases (and text representations can cover the same territory just as well) rather than doing what they should do - allow varied representations of programs.
Yes! All language, whether natural or programming, can have two primary structures: semantic and thematic (these are terms from Linguistics). Thematic structure (very roughly) refers to the effect of the writer, the medium, and the reader/s, which explains why one semantic structure can be represented in a variety of ways.
