Awesome! This has long been a dream of mine, but I never solved the problem of creating a better syntax than BNF grammars etc.

I don't know if we have the same goals, but my end-goal was to have some treelike serialization (JSON/XML) but a canonical editor which would display in whatever you were most familiar with (Lisp, Python, Haskell, C-ish). The limitation would be that you'd have to store metadata-ish stuff on the tree to handle custom indentations that don't follow some canonical style guide.