Just (as in 'only') change the (internal) representation of source code from character sequences to something that doesn't need a complex parsing process. In other words, eliminating the concept of syntax from language design, while keeping other language properties intact (could even use e.g. an LLVM back-end), allowing whoever desires it to write their own editors etc. as always.
(This is different from eliminating text: IMO, the visualization should remain primarily text. I say to eliminate syntax in the sense that the text 'visualization' no longer has a connection with semantics, nor any grammatical constraints.)
The reason I say 'just' change that: there are other systems structured to render AST-like structures (rather than parsing), but they are integrated with particular software systems. We need a general purpose alternate format with a similar independence of any project that 'character sequences' have for current source code.
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I have a proposal for one that's very simple and general: represent languages as graphs of language constructs, and represent particular programs as paths through a language graph. More details at [1].
Making this substitution we can: throw out parsing, allow easy customization of language appearance (including things that would traditionally fall under 'syntax'), have much easier access to language insight (source representation is directly in terms of a language definition), give far easier to access to experimenting with language UX ideas, and more.
I'd love to hear thoughtful feedback on this. I will likely invest a solid amount of time/effort into building a prototype before long, so if someone can spot a potential weakness that I've missed, I'd be forever grateful.
(That said, please attempt at least a small amount of charity in reading: I wrote this in 2015 and most all I've gotten is people replying, "visual programming doesn't work" —even though it's expressly not advocating visual programming. I believe I really am talking about something fairly new here: and I am more than willing to listen if I'm mistaken. I have too many projects already; I have no need for this to work out. I just haven't been able to disprove it as... not being what it appears to be, and so I've felt an obligation to see it through for a long time.)
[1] http://westoncb.blogspot.com/2015/06/how-to-make-view-indepe...